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andy

CLUB ADMIN

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Blog Entries posted by andy

  1. Right then...

    Club Updates · andy · 05/13/26 02:11

    After 3.5+ years living over 5000 miles away, we’re finally coming home to the UK. And that means becoming active with MK2CAV.COM properly again.
     
    Somehow, our weird little website started back in 1998 is STILL alive. Which honestly feels slightly miraculous considering the modern internet now mainly consists of doomscrolling, AI slop cat ninjas, ragebait and “what wheels fit?” posted 140 times a day by people who apparently fear the search function more than terminal rust. Comparatively - MK2CAV.COM may be ancient, but it matters. Today, socials posts vanish with the swipe of a thumb and are forgotten 2 minutes later, while old forum threads from 2004 are STILL helping people keep these cars alive today.
    Somewhere on the forum there are still 17-page arguments on Weber conversions vs original Varajet carbs that remain more useful than 99% of modern social media.
     
    And honestly… our archive of human experience (and even joy) matters of now more than ever.  Because MK2CAV.COM was never just a website, classifieds page, or somewhere to argue about wheel offset and dashboard rattles
     
    It became:
    an archive and wealth of technical knowhow.  a place that documented restorations and saved cars a social club and occasionally group therapy for people emotionally attached to rusty 1980s Vauxhalls  
    But equally, the reality is our previous club and hosting setup simply is not sustainable long-term given membership numbers and general cost-of-living madness.
    So over the coming months we’ll be:
    reviewing forum and club operations looking at the future role of the website preserving our archives properly modernising and streamlining further rethinking merch, stickers and perks and moving more strongly towards preserving a whole bygone era of motoring  
    Importantly:
    That does NOT mean deleting the forum or abandoning what made the club special. Quite the opposite.
    The goal is to preserve 20+ years of history, guides, photos, technical resources and friendships properly while also making the club feel alive again.
     
    Because while Facebook groups can absolutely continue doing their thing, I still believe there’s still room for something deeper for those who want more meaningful engagement:
    road trips restorations technical writeups random roadside and barn-find saves retro reminiscing and the strange things that only seem to happen when you own an 80s Vauxhall  
    The internet changed. Forums died.
    Photobucket murdered half our old build threads.
    Social media replaced conversations with algorithms.
    And now half the internet appears to be mainly bots stirring up hatred while AI-generated memes lull us into a collective stupor.  
    Yet somehow this place still survives, and it reminds me of happier more outgoing times, before social media made us all feel "too busy". 
     
    Like our cavs, the club  site is a bit rusty. Occasionally broken.
    Held together largely by stubbornness and irrational optimism (also like our cavs). 
     
    So, one thing I’ve also realised recently is that the club was always strongest when it had its own content and media personality, not just FB scrolling pictures of cavs in fields.
    So  I’ve started creating retro-themed club artwork and posters for paid members inspired by:
    1980s / GM culture old VHS action films dealer graphics and tax discs period brochures retro magazines motorway service stations at 2am and general nostalgic nonsense  
    If you’re a paid-up member, PM me on MK2CAV.COM to request:
    personalised avatars  / retro poster magazine cover / pop-culture parody scenes and other club-style artwork featuring your Cav  
     
     
    (Completely unique and free for you to use on social media, clothing, garages, banners or wherever else you wish to proudly display your questionable life choices and Cavalier-flavoured love of 1980s motoring).
    Subject of course to my time and availability while relocating half my life back across the planet*
     
    Also… IMPORTANT!
    Our annual VBOA Sywell weekend is nearly upon us.
    So if you want to attend with the club, check the forum events section and get involved. I’m genuinely chuffed that all the club admins (even me!) should be there this year.
    Let’s see who else still has enough unburnt petrol fumes and irrational optimism left in them to make the trip.
    (Mk1, Mk2, Mk3 Cav or no Cav at all - you’re always welcome.)
     
    And finally:
    thank you to YOU for sticking around.
    At present there are at least five MK2 Cavalier Facebook groups doing similar things. And honestly, that’s absolutely fine. Some were even founded by old members from this site.
    In a world increasingly lacking shared pursuits and common interests, I genuinely think the more the merrier.
     
    But we are now:
    27 years for the club.
    45 years for the Mk2 Cavalier itself.
     
    And somehow it’s now only 5 years until the Mk2 turns 50, which is frankly terrifying.
    Still… that feels like enough time to keep the life-support machine pumping a little longer.
     
    Forums are supposedly dead.
    Small car clubs are supposedly dead.
    And AI bots, dead internet theory and endless scrolling are making even good Facebook groups increasingly disposable.
    But MK2CAV.COM was never really about the cars.
     
    It was about preserving a strange little slice of the 1980s and the friendships that came about from our quirky obsession. 
    So somehow, nearly 30 years later… we’re still here. Still trying to keep these rusty old boxes on the road.
    And honestly?
     
    We’re going to have a bloody good time doing so for the next few years.
    Everyone is invited.
    Andy
    c/o MK2CAV.COM




  2. Bosch Motronic Engine Codes

    Engines · andy · 09/24/21 22:54

    Bosch Motronic Systems

    12 Initiation of diagnosis. n/a
    13 Oxygen sensor No change in voltage/open circuit.
    14 Coolant Temperature Sensor (CTS) Low voltage
    15 Coolant Temperature Sensor (CTS) High voltage
    16 Knock sensor 1 No change in voltage
    17 Knock sensor 2 No change in voltage
    18 Knock control unit No signal, Engine Control Unit (ECU) fault
    19 RPM signal (crankshaft sensor) Incorrect signal
    21 Throttle position sensor High voltage
    22 Throttle position sensor Low voltage
    23 Knock sensor module n/a
    24 Vehicle speed sensor (VSS) No signal
    25 Injector valve 1 High voltage
    26 Injector valve 2 High voltage
    27 Injector valve 3 High voltage
    28 Injector valve 4 High voltage
    28 Fuel pump relay Low voltage
    29 Injector valve 5 High voltage
    31 Engine RPM signal (crankshaft sensor) No signal
    32 Injector valve 6 High voltage
    32 Fuel pump relay High voltage
    33 Inlet manifold pressure sensor Voltage too high
    34 Exhaust Gas Re-circulation (EGR) valve Voltage too high
    34 Manifold Absolute Pressure (MAP) sensor Low voltage
    35 Idle Speed Control Valve (ISCV) Poor or no idle speed control
    36 Incorrect RON/Octane setting Damaged RON plug or bad connection.
    37 Engine self-diagnosis (fault code light) Low voltage
    38 Oxygen sensor Voltage low (1990 model year on)
    39 Oxygen sensor Voltage high (1990 model year on)
    41 Vehicle speed sensor (VSS) Low voltage
    41 1 gear ident switch (C20LET systems) Low voltage
    41 EST Line coil cylinder 2&3 (M2.8/XEV systems) High voltage
    42 Vehicle speed sensor (VSS) High voltage
    42 1 gear ident switch (C20LET systems) High voltage
    42 EST Line coil cylinder 2&3 (M2.8 / XEV systems) High voltage
    43 Linear EGR system (XEV systems) Faulty
    44 Oxygen sensor Air/fuel mixture too lean (weak)
    45 Oxygen sensor Air/fuel mixture too rich
    46 Air pump relay High voltage
    47 Air pump relay Low voltage
    47 Linear EGR Position (XEV systems) Faulty
    48 Battery voltage Low voltage
    49 Battery voltage High voltage
    51 ECU Programmable memory PROM error, hardware failure
    52 Engine check light; final stage (fault code light) High voltage
    53 Fuel pump relay Low voltage
    54 Fuel pump relay High voltage
    55 Engine Control Unit (ECU) fault Renew Engine Control Unit (ECU)
    56 Idle Speed Control Valve (ISCV) Short to earth
    57 Idle Speed Control Valve (ISCV) Interruption
    59 Inlet manifold valve 1 Low voltage
    61 Fuel Tank Vent Valve (FTVV) Low voltage
    62 Fuel Tank Vent Valve (FTVV) High voltage
    63 Inlet manifold valve 1 High voltage
    63 EST Line coil cylinder 2&3 (M2.8 / XEV systems) Low voltage
    64 EST Line coil cylinder 1&4 (M2.8 / XEV systems) Low voltage
    65 Carbon Monoxide (CO) potentiometer Low voltage
    66 Carbon Monoxide (CO) potentiometer High voltage
    67 Throttle valve switch - idle position switch Low voltage - switch not opening
    68 Throttle Switch (TS) - idle contact Idle switch not opening
    69 Air Temperature Sensor (ATS) Low voltage
    71 Air Temperature Sensor (ATS) High voltage
    72 Throttle Switch (TS) - full load contact High voltage - Full load switch not running
    73 Air Flow Sensor (AFS) Low voltage
    74 Air Flow Sensor (AFS) High voltage
    75 Transmission switch - torque control Low voltage
    76 Automatic Transmission (AT) torque control Engaged long, ignition ****** long
    79 Traction control unit Incorrect ignition/injector cut-off
    81 Injector valve 1 Low voltage
    82 Injector valve 2 Low voltage
    83 Injector valve 3 Low voltage
    84 Injector valve 4 Low voltage
    85 Injector valve 5 Low voltage
    86 Injector valve 6 Low voltage
    87 Air Conditioning (AC) cut off relay Low voltage
    88 Air Conditioning (AC) cut off relay High voltage
    89 Oxygen sensor heater Low voltage
    91 Oxygen sensor heater High voltage
    92 Camshaft sensor failure (XEV systems) Faulty
    93 Hall Effect Switch (HES) Low voltage
    94 Hall Effect Switch (HES) High voltage
    95 Hot start valve Low voltage
    96 Hot start valve High voltage
    97 Traction control unit - ignition/injection cut off Incorrect signal - high voltage
    98 Oxygen sensor Open circuit, wiring break
    99 Code unknown n/a
    113 Turbo boost control Boost presure high, out of range
    114 Idle boost valve Above upper limit
    115 Full boost pressure Below lower limit
    116 Boost pressure Above upper limit
    117 Wastegate valve Low voltage
    118 Wastegate valve High voltage
    121 Oxygen sensor 2 Lean exhaust, weak mixture
    122 Oxygen sensor 2 Rich mixture/exhaust
    123 Inlet manifold valve 1 Blocked
    124 Inlet manifold valve 2 Blocked
    132 Exhaust Gas Re-circulation (EGR) valve Incorrect signal
    133 Exhaust Gas Re-circulation (EGR) valve 2 High voltage
    134 Exhaust Gas Re-circulation (EGR) valve 2 Low voltage
    135 'Check engine' lamp (fault code lamp) Low voltage
    136 Engine Control Unit (ECU) n/a
    137 Engine Control Unit (ECU) box High temperature
    141 Secondary air pump Not enough air
    142 Secondary air pump Air without pump
    143 Immobiliser function in ECU No or incorrect signal
    144 No immobiliser signal recived Faulty unit or break in wiring
    145 Incorrect immobiliser signal received Faulty unit or break in wiring
  3. Put this together for my 20XE from a service manual. Found the entry for the 2.5 on the Corsa forum. Hope it's of some use!
    Mods/Admins: Feel free to make additions / extensions / corrections.
    NB: The 4.1 version is first, followed by the later 2.5 catalysed version that also has a dizzy.  Not for coilpack / dispak  setups per se (sorry Greg!), but these were similar to the 2.5 version which follows the 4.1 version. 
    NB: Early 20XE's - These first valvers may have different loom colours, and the tamper screw on the CO2 pot is sometimes open to the air. These are pre-catalysed engines and are often referred to as "the fastest ones".  If you have a lambda or a cat, scroll down to 2.5...
    Bosch Motronic 4.1 operation ( 20XE Pre 1990 )
    The electronic system used to control the GM 8 valve engines (1987 to 1990) is labelled Motronic 4.1 and is a fully integrated EMS that controls primary ignition, fuelling and idle control from within the same ECU. In addition the ignition point and injection duration are jointly processed by the ECU so that the best moment for ignition and fuelling are determined for every operating
    condition. The injection function of the Motronic system is based on the well tried 'L' jetronic system, although a number of refinements have improved operation. A 35 pin connector and multi-plug connects the ECU to the battery, sensors and actuators.

    Basic ECU operation
    A permanent voltage supply is made from the vehicle battery to pin 18 of the ECU. This allows the self-diagnostic function to retain data of an intermittent nature. Once the ignition is switched on, a voltage supply to the ignition coil and to ECU pin 35 is made from terminal 87 of the main fuel injection relay.
    The majority of sensors (other than those that generate a voltage such the CAS and OS), are now provided with a 5.0 volt reference supply from a relevant pin on the ECU. When the engine is cranked or run, a speed signal from the CAS causes the ECU to earth pin 20 so that the fuel pump will run. Ignition and injection functions are also activated. All actuators (Injectors,
    ISCV, FTVV etc), are supplied with nbv from the main relay and the ECU completes the circuit by pulsing the relevant actuator wire to earth.

    Signal processing
    Basic ignition timing is stored in a two dimensional map and the engine load and speed signals determines the ignition timing.
    The main engine load sensor is the AFS and engine speed is determined from the CAS signal.
    Correction factors are then applied for starting, idle, deceleration and part and full-load operation. The main correction factor is engine temperature (CTS). Minor correction to timing and AFR are made with reference to the ATS and TS signals.
    The basic AFR is also stored in a two dimensional map and the engine load and speed signals determines the basic injection pulse value. Motronic calculates the AFR from the AFS signal and the speed of the engine (CAS).

    The AFR and the pulse duration are then corrected on reference to ATS, CTS, battery voltage and position of the TS. Other controlling factors are determined by operating conditions such as cold start and warm-up, idle condition, acceleration and deceleration.
    Motronic accesses a different map for idle running conditions and this map is implemented whenever the engine speed is at idle.
    Idle speed during all warm-up and normal hot running conditions are maintained by the ISCV. However, Motronic makes small adjustments to the idle speed by advancing or retarding the timing, and this results in an ignition timing that is forever changing during engine idle.

    Self Diagnostic function
    The Motronic 4.1 system has a self-test capability that regularly examines the signals from engine sensors and internally logs a code in the event of a fault being present. This code can be extracted from the Motronic Serial Port by a suitable Fault Code Reader. When the ECU detects that a fault is present, it earths pin 17 and the warning lamp on the dash will light. The lamp will
    stay lit until the fault is no longer present. If the fault clears, the code will remain logged until wiped clean with a suitable FCR, or until the engine has been started for more than 20 times when the fault code is self initialising. An ECU that retains codes for faults of an intermittent nature is a valuable aid to fault diagnosis.
    The codes emitted by the Motronic 4.1 ECU fitted to GM vehicles emit codes of the 'slow code' variety. This means that the codes can be extracted by connecting two pins in the SD (ALDL) plug together.
    In addition to the self-test capability, Motronic 4.1 has full limp home facilities. In the event of a serious fault in one or more of the sensors, the EMS will substitute a fixed default value in place of the defective sensor.
    This means that the engine may actually run quite well with failure of one or more minor sensors. Since the substituted values are those of a hot engine, cold starting and running during the warm-up period may be less than satisfactory. Also, failure of a major sensor, i.e. the AFS, will tend to make driving conditions less easy.

    Reference voltage
    Voltage supply from the ECU to many of the engine sensors is at a 5.0 volt reference level. This ensures a stable working voltage unaffected by variations in system voltage.
    The earth return connection for some engine sensors is made through an ECU pin that is not directly connected to earth. The ECU internally connects that pin to earth via one of the ECU pins that are directly connected to earth.

    Signal shielding
    To reduce RFI, the CAS uses a shielded cable. The shielded cable is connected to the main ECU earth wire at terminal 27 to reduce interference to a minimum.

    Crankshaft Sensor Ignition
    Data on load (AFS), engine speed (CAS), engine temperature (CTS) and throttle position (TS) are collected by the ECU, which then refers to a three dimensional digital map stored within its microprocessor. This map contains an advance angle for each operating condition, and thus the best ignition advance angle for a particular operating condition can be determined.

    Amplifier
    The Motronic amplifier contains the circuitry for switching the coil negative terminal at the correct moment to instigate ignition.
    The amplifier circuitry is contained within the ECU itself and the microprocessor contains a map containing the correct ignition dwell period for each condition of engine speed and battery voltage. One disadvantage of an internal amplifier, is that if the amplifier fails, the whole ECU must be renewed.

    Dwell
    Dwell operation in Motronic is based upon the principle of the 'constant energy current limiting' system. This means that the dwell period remains constant at around 4.0 to 5.0 ms, at virtually all engine running speeds. However, the dwell duty cycle, when measured in percent or degrees, will vary as the engine speed varies. A current limiting hump is not visible when viewing an oscilloscope waveform.

    Ignition coil
    The ignition coil utilises low primary resistance in order to increase primary current and primary energy. The amplifier limits the primary current to around 8 amps and this permits a reserve of energy to maintain the required spark burn time (duration).

    Distributor
    In the Motronic system, the distributor only contains secondary HT components (distributor cap, rotor and HT leads) and serves to distribute the HT current from the coil secondary terminal to each spark plug in firing order.

    Octane coding
    It is not possible to adjust the ignition timing on the Motronic 4.1 system. However, an octane coding plug is provided to enable the ECU to adopt different characteristics to suit various operating conditions.
    The ECU has been built with several different programs to cater for various circumstances, and selecting an alternative Octane Plug or setting will trigger a different program. The most obvious change is from leaded to unleaded fuel - or vice versa, when the ECU may alter the ignition timing and fuel map to cater for the changed conditions.
    Simply turning the standard 95/98 Octane Plug to its alternative position will fulfil the alternative condition. Other conditions may be fulfilled by fitting an alternative octane plugs - such as the 95/91. A number of other octane plugs are also available and
    depending upon the Octane Plug chosen, will cause fuel enrichment during acceleration, overall fuel enrichment throughout the engine speed range, timing ****** or an increase in idle speed. However, fitting alternative plugs should be approached with caution as the effects may be detrimental to good running and economy.

    Fuel injection
    The Motronic ECU contains a fuel map with an injector opening time for basic conditions of speed and load. Information is then gathered from engine sensors such as the AFS, CAS, CTS, and TS. As a result of this information, the ECU will look-up the correct injector pulse duration right across the engine rpm, load and temperature range.
    The Motronic 4.1 system is a multi-point injection system and pulses all injectors at the same time - i.e. simultaneously and twice per engine cycle. Half of the required fuel per engine cycle is injected at each engine revolution. During engine start from cold, the pulse duration and number of pulses (frequency) are increased to provide a richer air/fuel mixture.

    Fuel injectors
    The fuel injector is a magnetically operated solenoid valve that is actuated by the ECU. Voltage to the injectors is applied from the main relay and the earth path is completed by the ECU for a period of time (called pulse duration) of between 1.5 and 10 milliseconds. The pulse duration is very much dependant upon engine temperature, load, speed and operating conditions. When
    the magnetic solenoid closes, a back EMF voltage of up to 60 volts is initiated.
    The fuel injectors are mounted in the inlet stubs to the engine inlet valves so that a finely atomised fuel spray is directed onto the back of each valve. Since the injectors are all pulsed simultaneously, fuel will briefly rest upon the back of a valve before being drawn into a cylinder.

    Air Flow Sensor (AFS)
    The AFS is located between the air filter and the throttle body. As air flows through the sensor it deflects a vane (flap). The vane is connected to a wiper arm which wipes a potentiometer resistance track and so varies the resistance of the track. This allows a variable voltage signal to be returned to the ECU.
    Three wires are used by the circuitry of this sensor and it is often referred to as a three wire sensor. A 5 volt reference voltage is applied to the resistance track with the other end connected to the AFS earth return. The third wire is connected to the wiper arm.
    From the voltage returned, the ECU is able to calculate the volume of air (load) entering the engine and this is used to calculate the main fuel injection duration. To smooth out inlet pulses, a damper is connected to the AFS vane. The AFS exerts a major influence on the amount of fuel injected.

    ATSCO pot
    The CO pot mixture adjuster is a potentiometer that allows small changes to be made to the idle CO. A 5.0 volt reference voltage is applied to the sensor and connected to the AFS earth return circuit. The third wire is the CO pot signal.
    As the CO pot adjustment screw is turned the change in resistance returns a voltage signal to the ECU that will result in a change in CO. The CO pot adjustment only affects idle CO. Datum position is usually 2.50 volts. On catalyst equipped models, the CO pot has no effect and the CO is thus non-adjustable.

    CTSThrottle switch
    A throttle switch with dual contacts is provided to inform the ECU of idle position, deceleration, cruising and full-load (WOT) conditions. When the engine is at idle the idle contact is closed and the full-load contact is open. As the throttle is moved to the fully open position, the full-load contact closes and the idle contact becomes open. Under cruising conditions with a part-open
    throttle, both contacts are open. During full-load operation, the ECU provides additional enrichment.
    During closed throttle operation above a certain rpm (deceleration), the ECU will cut-off fuel injection. Injection will be reintroduced once the rpm returns to idle or the throttle is opened.

    ISCV
    The ISCV is a solenoid controlled actuator that the ECU uses to automatically control idle speed during engine warm-up and idle at normal operating temperature. Irrespective of engine temperature or engine load, the engine idle speed should remain at an almost constant level. The ISCV is located in a hose that connects the inlet manifold to the air filter side of the throttle plate.
    When an electrical load, such as headlights or heater fan etc are switched on, the idle speed would tend to drop. The ECU will sense the load and rotate the ISCV against spring tension to increase the air flow through the valve and thus maintain the idle speed at its previous level. When the load is removed, the ECU will pulse the valve so that the air flow is reduced. Normal idle speed of 780 to 850 rpm should be maintained under all cold and hot operating conditions. If the ISCV fails it will fail in a fail-safe position with the aperture almost closed. This will provide a basic idle speed.

    Relay
    The Motronic electrical system is controlled by a single system relay with dual contacts. A permanent voltage supply is made to relay terminal 30 from the battery positive terminal. When the ignition is switched on, a voltage supply is made to terminal 86 and this energises the first relay winding which is connected to earth. This causes the first relay contacts to close and terminal 30 is connected to the output circuit at terminal 87. A voltage supply is thus output at terminal 87. Terminal 87 supplies voltage to the injectors, ECU: t35, ISCV and the FTVV when fitted. In addition voltage is supplied to the second relay contact.
    When the ignition is switched on. the ECU briefly earths relay contact 85b at ECU terminal 20. This energises the second relay winding, which closes the second relay contact and connects voltage from terminal 30 to terminal 87b, thereby providing voltage to the fuel pump circuit. After a second or so, the ECU opens the circuit and the pump stops. This brief running of the fuel pump
    allows pressure to build within the fuel pressure lines, and provides for an easier start.
    The second circuit will then remain open until the engine is cranked or run. Once the ECU receives a speed signal from the CAS, the second winding will again be energised by the ECU, and the fuel pump will run until the engine is stopped.

    Fuel pressure system
    A roller type fuel pump, driven by a permanent magnet electric motor mounted close to the fuel tank, draws fuel from the tank and pumps it to the fuel rail via a fuel filter. The pump is of the 'wet'
    variety in that fuel actually flows through the pump and the electric motor. There is no actual fire risk because the fuel drawn through the pump is not in a combustible condition.
    Mounted upon the armature shaft is an eccentric rotor holding a number of pockets arranged around the circumference – each pocket containing a metal roller. As the pump is actuated, the rollers are flung outwards by centrifugal force to act as seals. The fuel between the rollers is forced to the pump pressure outlet.
    Fuel pressure in the fuel rail is maintained at a constant 2.5 bar by a fuel pressure regulator. The fuel pump normally provides much more fuel than is required, and surplus fuel is thus returned to the fuel tank via a return pipe. In fact, a maximum fuel pressure in excess of 5 bar is possible in this system. To prevent pressure loss in the supply system, a non-return valve is provided in the fuel pump outlet. When the ignition is switched off, and the fuel pump ceases operation, pressure is thus maintained for some time.

    Fuel pressure regulator
    The pressure regulator is fitted on the outlet side of the fuel rail and maintains an even pressure of 2.5 bar at the injectors during idle conditions. The pressure regulator consists of two chambers separated by a diaphragm. The upper chamber contains a spring which exerts pressure upon the lower chamber and closes off the outlet diaphragm. Pressurised fuel flows into the lower
    chamber and this exerts pressure upon the diaphragm. Once the pressure exceeds 2.5 bar, the outlet diaphragm is opened and excess fuel flows back to the fuel tank via a return line.
    A vacuum hose connects the upper chamber to the inlet manifold so that variations in inlet manifold pressure will not affect the amount of fuel injected. This means that the pressure in the rail is always at a constant pressure above the pressure in the inlet manifold. The quantity of injected fuel thus depends solely on injector opening time, as determined by the ECU, and not on a variable fuel pressure.
    At idle speed with the vacuum pipe disconnected, or with the engine stopped and the pump running, or at WOT the system fuel pressure will be approximately 2.5 bar. At idle speed (vacuum pipe connected), the fuel pressure will be approximately 0.5 bar under the system pressure.
    Catalytic Converter
    Versions with a Catalytic Converter will also be fitted with an oxygen sensor so that closed loop control of emissions can be implemented. The OS is heated so that it will reach optimum operating temperature as quickly as possible after the engine is started. The OS heater supply is made from the fuel injection relay terminal number 87b. This ensures that the heater will only
    operate whilst the engine is running.
    An FTVV and activated carbon canister is also be employed to aid evaporative emission control. The carbon canister stores fuel vapours until the FTVV is opened by the EMS under certain operating conditions. Once the FTVV is actuated by the EMS, fuel vapours are drawn into the inlet manifold to be burnt by the engine during normal combustion.
     

    Motronic 2.5 operation (all 20XE/C20XE engines post 1990, with a distributor)
    Motronic 2.5 is an enhancement of the Motronic 4.1 EMS fitted to earlier Vauxhall and Opel vehicles. It was first fitted in the 1990 model year (late 1989) and is a fully integrated system that controls primary ignition, fuelling and idle control from within the same ECU. It is normally only fitted to 16 valve GM engines. The control unit contains three microprocessors for:
    general control unit operation
    sequential injection
    knock control
    The Motronic ignition point and injection duration are jointly processed by the ECU so that the best moment for ignition and fuelling are determined for every operating condition. The injection function of the Motronic system is based on the well tried 'L' jetronic system, although a number of refinements have improved operation. A 55 pin connector and multi-plug connects the ECU to the battery, sensors and actuators.

    Basic ECU operation
    A permanent voltage supply is made from the vehicle battery to pin 18 of the ECU. This allows the self-diagnostic function to retain data of an intermittent nature. Once the ignition is switched on, a voltage supply to the ignition coil and to ECU pin 27 is made from the ignition switch. This causes the ECU to connect pin 36 to earth, so actuating the main fuel injection relay. A relay switched voltage supply is thus made to ECU pin 37, from terminal 87 of the main fuel injection relay.
    The majority of sensors (other than those that generate a voltage such the CAS, KS and OS), are now provided with a 5.0 volt reference supply from a relevant pin on the ECU. When the engine is cranked or run, a speed signal from the CAS causes the ECU to earth pin 3 so that the fuel pump will run. Ignition and injection functions are also activated. All actuators (Injectors, ISCV, FTVV etc), are supplied with nbv from the main relay and the ECU completes the circuit by pulsing the relevant actuator wire to earth.

    Signal processing
    Basic Ignition timing is calculated from the ignition map and engine load determines the basic injection pulse value. Correction factors are then applied for starting, idle, deceleration, part and full-load operation. The main engine load sensor is the AFS and the main correction factor is engine temperature.

    Reference voltage
    Voltage supply from the ECU to many of the engine sensors is at a 5.0 volt reference level. This ensures a stable working voltage unaffected by variations in system voltage.
    The earth return connection for most engine sensors is made through an ECU pin that is not directly connected to earth. The ECU internally connects that pin to earth via one of the ECU pins that are directly connected to earth.

    ECU coding wires (where fitted)
    Some vehicles equipped with Motronic 2.5 have certain ECU pins allocated as coding earths. The open circuit voltage at these pins is either nbv or at 5.0 volt reference level. Connection of the pin to earth indicates to the ECU that the vehicle is
    equipped with certain equipment. The non cat vehicle has pin 20 connected to earth and the catalyst equipped vehicle has pin 20 open circuit. The vehicle with AT has pin 21 connected to earth and the vehicle with MT has pin 21 open circuit.

    Signal shielding
    To reduce RFI, a number of sensors (i.e. CAS, HES, KS, amplifier and OS) use a shielded cable. The shielded cable is connected to the main ECU earth wire at terminal 19 to reduce interference to a minimum.

    Crankshaft Sensor
    Ignition Amplifier
    The amplifier contains the circuitry for switching the coil negative terminal at the correct moment to instigate ignition. The signal received by the amplifier from the trigger is of an insufficient level to complete the necessary coil switching. The signal is thus amplified to a level capable of switching the coil negative terminal.

    Unlike earlier Vauxhall/ Motronic systems (in which the amplifier was contained in the ECU itself), Motronic 2.5 utilises a separate amplifier mounted on a heat sink plate adjacent to the coil. The ECU thus calculates the correct ignition dwell time and timing advance from data received from its sensors, and sends a signal to the amplifier which then switches the coil negative terminal. The advantage of a separate amplifier, is that if the amplifier fails, it is less costly to renew than a new ECU.

    Dwell operation in Motronic is based upon the principle of the 'constant energy current limiting' system. This means that the dwell period remains constant at around 4.0 to 5.0 ms, at virtually all engine running speeds. However, the dwell duty cycle, when measured in percent or degrees, will vary as the engine speed varies. A current limiting hump is not visible when viewing an oscilloscope waveform.

    Ignition coil
    The ignition coil utilises low primary resistance in order to increase primary current and primary energy. The amplifier limits the primary current to around 8 amps and this permits a reserve of energy to maintain the required spark burn time (duration).

    Distributor
    In the Motronic system, the distributor only contains secondary HT components (distributor cap, rotor and HT leads) and serves to distribute the HT current from the coil secondary terminal to each spark plug in firing order.

    Knock sensor
    The optimal ignition timing (at engine speeds greater than idle) for a given high compression engine is quite close to the point of onset of knock. However, running so close to the point of knock occurrence, means that knock will certainly occur on one or more cylinders at certain times during the engine operating cycle. Since knock may occur at a different moment in each individual cylinder, Motronic 2.5 employs the Knock Control unit – KCU (in the ECU) to pinpoint the actual cylinder or cylinders that are knocking. The Knock Sensor is mounted on the engine block and consists of a piezoceramic measuring element that responds to engine noise oscillations. This signal is converted to a voltage signal by the Knock Sensor and returned to the KCU for evaluation and action. Tests have shown that the 20XE & C20XE engines have a knocking frequency in the 15kHz frequency band. The KCU will analyse the noise from each individual cylinder and set a reference noise level for that cylinder based upon the average of the last 16 phases. If the noise level exceeds the reference level by a certain amount, the KCU identifies the presence of engine knock.
    Initially, timing will occur at its optimal ignition point. Once knock is identified, the Knock Control microprocessor retards the ignition timing for that cylinder or cylinders by 3ш. Approximately 2 seconds after knocking ceases (20 to 120 knock- free combustion cycles), the timing is advanced in 0.75ш increments until the reference timing value is achieved or knock occurs once more when the timing is retarded or This procedure continually occurs so that all cylinders will consistently run at their optimum timing.
    If a fault exists in the Knock Control processor, Knock control sensor or wiring, an appropriate code will be logged in the self-diagnostic unit and the ignition timing retarded by 10.5ш by the LOS program.

    Cylinder Identification
    In earlier Motronic systems the ECU does not recognise number one cylinder or indeed even the firing order. This is because it is actually unnecessary. When the crankshaft or distributor provides a timing signal, the correct cylinder is identified by the mechanical position of the crankshaft, camshaft, valves and ignition rotor. In systems where the injectors fire simultaneously,
    then the fuel will sit upon the back of an inlet valve until the valve opens.
    Since fuel injection occurs on an individual cylinder basis in Motronic 2.5, the ECU must be informed on which stroke a cylinder is actually on. This is achieved by a cylinder identification sensor attached to the distributor and which works on the Hall-Effect principle. The sensor identifies number one cylinder, and returns a signal to the ECU from which the identification
    of all the other cylinders can be calculated. The distributor is attached to the exhaust camshaft (the engine is DOHC in configuration) .

    Octane coding
    Because of the sophistication of the KCU and timing control an octane coding plug is not considered necessary for the 20XE & C20XE engines. Octane adjustment is automatically selected according to operating conditions. Motronic 2.5 is programmed with two different timing maps. These are Low Octane Number Map (more retarded timing) and High Octane Number Map (more advanced dwell angle). The KCU selects the appropriate map according to the following conditions. Once knocking combustion of more than 50 have occurred, the KCU switches to the Low Octane Map. Once approximately 8.5 minutes of knock-free operation have passed, the KCU switches to the High Octane Map.

    Fuel injection determination
    The ECU or vehicle computer is programmed with a basic injector map. Information is then gathered from engine sensors such as the AFS, Crankshaft Sensor, CTS, and TS. As a result of this information, the ECU will look-up the correct injector pulse duration right across the engine rpm, load and temperature range.

    Fuel injection
    The Motronic 2.5 system is a multi-point injection system and pulses the injectors sequentially - i.e. in firing order and once perengine cycle. Each injector is connected to the ECU via a separate ECU pin). Earlier Motronic systems (i.e. 4.1 and 1.5) pulseall injectors at the same time - i.e. simultaneously and twice per engine cycle.
    During engine start from cold, the pulse duration and number of pulses (frequency) are increased to provide a richer air/fuel mixture.

    Fuel injectors
    The fuel injector is a magnetically operated solenoid valve that is actuated by the ECU. Voltage to the injectors is applied from the main relay and the earth path is completed by the ECU for a period of time (called pulse duration) of between 1.5 and 10 milliseconds. The pulse duration is very much dependant upon engine temperature, load, speed and operating conditions.
    When the magnetic solenoid closes, a back EMF voltage of up to 60 volts is initiated.
    The fuel injectors are mounted in the inlet stubs to the engine inlet valves so that a finely atomised fuel spray is directed onto the back of each valve. Since the injectors are all pulsed simultaneously, fuel will briefly rest upon the back of a valve before being drawn into a cylinder.

    Hot Wire Air mass meter (AFS)
    Motronic 2.5 also uses a Hot Wire airflow sensor to measure the mass of air entering engine. From the air mass, an accurate fuel injection pulse can then be calculated. Hot Wire is a very accurate method of calculating the engine load (air input) and excludes the need for additional sensors to measure air temperature and air pressure. Automatic compensation for altitude is
    thus provided. The absence of moving parts improves reliability and lessens maintenance requirements.

    Essentially, the hot wire is so called because a heated wire is placed in the air intake. As air passes over the wire it has a cooling effect in proportion to the mass of air. As airmass increases or decreases according to engine load, the ECU adjusts the current flow to maintain the wire at its original resistance and temperature. By measuring the change in current flow, the
    ECU is able to determine the mass of air flow into the engine. As the current varies on the signal wire, so does the voltage and an indication of load can be assessed by measuring the variable voltage signal. Voltage is applied to the sensor from the system relay.
    If a fault exists in the Hot Wire AFS or wiring, an appropriate code will be logged in the self-diagnostic unit and a substitute value provided by the LOS program.

    Hot wire burn-off
    Over a period of time, deposits tend to build-up upon the hot wire and this can lead to contamination of the hot-wire. This is
    avoided with a `burn-off' function controlled by the ECU during engine shutdown. Approximately four seconds after the engine has been switched off, the ECU rapidly pulses the hot-wire terminal
    CO pot
    The CO pot mixture adjuster is a three wire potentiometer that allows small changes to be made to the idle CO. A 5.0 volt reference voltage is applied to the sensor and connected to the AFS earth return circuit. The third wire is the CO pot signal.
    As the CO pot adjustment screw is turned the change in resistance returns a voltage signal to the ECU that will result in a change in CO. The CO pot adjustment only affects idle CO. On catalyst equipped models, the CO pot has no effect and the CO is thus non-adjustable.

    CTS
    Throttle switch
    A throttle switch with dual contacts is provided to inform the ECU of idle position, deceleration, cruising and full-load (WOT) conditions. When the engine is at idle the idle contact is closed and the full-load contact is open. As the throttle is moved to the fully open position, the full-load contact closes and the idle contact becomes open. Under cruising conditions with a part-open throttle, both contacts are open. During full-load operation, the ECU provides additional enrichment. During closed throttle operation above a certain rpm (deceleration), the ECU will cut-off fuel injection. Injection will be reintroduced once the rpm returns to idle or the throttle is opened.

    ISCV
    The ISCV is a solenoid controlled actuator that the ECU uses to automatically control idle speed during normal idle and during engine warm-up. The ISCV is located in a hose that connects the inlet manifold to the air filter side of the throttle plate.
    When an electrical load, such as headlights or heater fan etc are switched on, the idle speed would tend to drop. The ECU will sense the load and rotate the ISCV against spring tension to increase the air flow through the valve and thus increase the idlespeed. When the load is removed, the ECU will pulse the valve so that the air flow is reduced. Normal idle speed should be maintained under all cold and hot operating conditions. If the ISCV fails it will fail in a fail-safe position with the aperture almost closed. This will provide a basic idle speed.

    Relays
    The Motronic electrical system is controlled by a single system relay with dual contacts. A permanent voltage supply is made to relay terminals 30 and 86 from the battery positive terminal. When the ignition is switched on, the ECU earths terminal 85 through ECU terminal number 36 which energises the first relay winding. This causes the first relay contacts to close and terminal 30 is connected to the output circuit at terminal 87. A voltage supply is thus output at terminal 87. Terminal 87 supplies voltage to the injectors, ECU terminal 37, ISCV and the FTVV when fitted. In addition voltage is supplied to the second relay contact.

    When the ignition is switched on. the ECU briefly earths relay contact 85b at ECU terminal 3. This winding, which closes the second relay contact and connects voltage from terminal 30 to terminal 87b, thereby providing voltage to the fuel pump circuit. After approximately one second, the ECU opens the circuit and the pump stops. This brief running of the fuel pump allows pressure to build within the fuel pressure lines, and provides for an easier start.

    The second circuit will then remain open until the engine is cranked or run. Once the ECU receives a speed signal from the Crankshaft Sensor, the second winding will again be energised by the ECU, and the fuel pump will run until the engine is stopped.

    Fuel pressure system
    A roller type fuel pump, driven by a permanent magnet electric motor mounted close to the fuel tank, draws fuel from the tank and pumps it to the fuel rail via a fuel filter. The pump is of the 'wet' variety in that fuel actually flows through the pump and the electric motor. There is no actual fire risk because the fuel drawn through the pump is not in a combustible condition.
    Mounted upon the armature shaft is an eccentric rotor holding a number of pockets arranged around the circumference – each pocket containing a metal roller. As the pump is actuated, the rollers are flung outwards by centrifugal force to act as seals. The fuel between the rollers is forced to the pump pressure outlet. Fuel pressure in the fuel rail is maintained at a constant 2.5 bar by a fuel pressure regulator. The fuel pump normally provides much more fuel than is required, and surplus fuel is thus returned to the fuel tank via a return pipe. In fact, a maximum fuel pressure in excess of 5 bar is possible in this system. To prevent pressure loss in the supply system, a non-return valve is provided in the fuel pump outlet. When the ignition is switched off, and the fuel pump ceases operation, pressure is thus maintained for some time.

    Fuel pressure regulator
    The pressure regulator is fitted on the outlet side of the fuel rail and maintains an even pressure of 2.5 bar in the fuel rail. The pressure regulator consists of two chambers separated by a diaphragm. The upper chamber contains a spring which exerts
    pressure upon the lower chamber and closes off the outlet diaphragm. Pressurised fuel flows into the lower chamber and this exerts pressure upon the diaphragm. Once the pressure exceeds 2.5 bar, the outlet diaphragm is opened and excess fuel flows back to the fuel tank via a return line.
    A vacuum hose connects the upper chamber to the inlet manifold so that variations in inlet manifold pressure will not affect the amount of fuel injected. This means that the pressure in the rail is always at a constant pressure above the pressure in the inlet manifold. The quantity of injected fuel thus depends solely on injector opening time, as determined by the ECU, and not
    on a variable fuel pressure.
    At idle speed with the vacuum pipe disconnected, or with the engine stopped and the pump running, or at WOT the system fuel pressure will be approximately 2.5 bar. At idle speed (vacuum pipe connected), the fuel pressure will be approximately 0.5 bar under the system pressure.

    Self Diagnostic function
    The Motronic 2.5 system has a self-test capability that regularly examines the signals from engine sensors and internally logs a code in the event of a fault being present. This code can be extracted from the Motronic serial port by a suitable Fault Code Reader. When the ECU detects that a fault is present, it earths pin 17 and the warning lamp on the dash will light. The lamp
    will stay lit until the fault is no longer present. If the fault clears, the code will remain logged until wiped clean with a suitable FCR, or until the engine has been started for more than 20 times when the fault code is self initialising. An ECU that retains codes for faults of an intermittent nature is a valuable aid to fault diagnosis.

    In addition to the self-test capability, Motronic 2.5 has full limp home facilities. In the event of a serious fault in one or more of the sensors, the EMS will substitute a fixed default value in place of the defective sensor.
    This means that the engine may actually run quite well with failure of one or more minor sensors. Since the substituted value are those of a hot engine, cold starting and running during the warm-up period may be less than satisfactory. Also, failure of a major sensor, i.e. the AFS, will tend to make driving conditions less easy.

    Catalytic Converter and emission control Versions with a Catalytic Converter will also be fitted with an oxygen sensor so that closed loop control of emissions can be implemented. The OS is heated so that it will reach optimum operating temperature as quickly as possible after the engine is started. The OS heater supply is made from the fuel injection relay terminal number 87b. This ensures that the heater will only operate whilst the engine is running.
    An FTVV and activated carbon canister are also being employed to aid evaporative emission control. The carbon canister stores fuel vapours until the FTVV is opened by the EMS under certain operating conditions. Once the FTVV is actuated by the EMS, fuel vapours are drawn into the inlet manifold to be burnt by the engine during normal combustion.

  4. F18 5th Gear into an F20

    · andy · 10/29/15 08:22

    The idea of this mod is to give you better motorway cruising by fitting a WR 5th gear while keeping the decent acceleration of a CR 1st - 4th.
     
    You could just go all fancy like Andy and fit an F28 but this is cheaper and gives you lower revs in 5th than the F28 in 6th.
     
    I'm fitting a WR gear to my F20 but its the same procedure if you want to fit an F16WR 5th into your F16CR or if your fitting an
    F20 gear cluster into your F16 housing this is a worthwhile mod.
     
    F16s all share the same selector forks so swapping between them is easy.
    If your fitting an F20 cluster its easier to use an F18WR 5th as the selector forks are the same between the
    F18 and F20 but not with the F16
     
    If you dont feel confident taking your gearbox apart the please dont start.
    This is fairly simple to do but its still the inside of a gearbox 
     
    1- Remove the end cover of the box. This is the inner ring of 11/13mm bolts
     

     
    2- now looking at the gears you need to:
     
    Remove the two circlips arrowed in GREEN
    Remove the two 5.5mm allen bolts that are arrowed in YELLOW
    The left hand gear can now be removed by gently prying it from behind with a screwdriver. It is in a few parts so keep hold of it as you pull it off keeping the selector fork with it and being very carefull not to let the two bronze bushes (circled in RED) fall out.
     

     
    3- Removing the left hand gear requires a puller but it does just slide off once the circlip is removed.
     

     
    This is what your left with. Be gentle with it and keep it absolutely clean

    Removing the F20 one is exactly the same and refitting is the opposite. If your doing this with the box still in the car jack up the passenger side only so you don't loose gear oil.

  5. Gear Ratios

    · andy · 10/29/15 08:26

    3-Speed Automatic
     
    1st  2.48
    2nd 1.6
    3rd  1.0
     
     
    1300 Early 4 Speed:
     
    1st 3.636
    2nd 2.211
    3rd 1.429
    4th 0.969
     
    Final Drive Gear 4.18 to 1
     
    1600 Early 4 Speed:
     
    1st 3.545
    2nd 2.158
    3rd 1.370
    4th 0.971
     
    Final Drive Gear 3.74 to 1
     
    1600 Early 5 Speed SRi
     
    1st 3.42
    2nd 1.95
    3rd 1.28
    4th 0.89
    5th 0.71
     
    Final Drive 3.47 to 1
     
     
    Mid Spec SRi 1800i
     
    1st 3.42
    2nd 2.16
    3rd 1.48
    4th 1.12
    5th 0.89
     
    Final Drive 3.94 to 1
     
    Late Spec 2.0 SRi's
     
    1st 3.4
    2nd 2.2
    3rd 1.5
    4th 1.1
    5th 0.89
     
    Final Drive 3.55 to 1
     
    Often used others:
     
    F20
     
    1st 3.55 
    2nd 2.16 
    3rd 1.48
    4th 1.13
    5th 0.89
     
    Final Drive 3.55 to 1
     
    F28
     
    1st 3.57
    2nd 2.16
    3rd 1.45
    4th 1.10
    5th 0.89
    6th 0.74
     
    Final drive ratio: 3.72:1 (front)
    Feel free to add new data and box codes for other models and I will flesh-out the data above. This is just a start.

  6. Rear Disc Conversion

    · andy · 10/29/15 08:17

    This is a basic how-to on converting to rear disc brakes using mk3 cav or astra hubs. This is a very simple swap and is very worthwhile since the disc setup brings both better braking and easier maintenance.
     
    Now if your thinking of doing this I assume you can remove the beam yourself so im not going through that. The rear brakes will need to be bled afterward and there is a small bit of welding needed on the handbrake adjuster.
     
    The easiest way to do it it to get your hands on a complete mk3 cav rear beam complete. This just bolts straight on without any modification leaving you with only the handbrake cable to sort.
     
    If however you can't get one of those but can get the disc hubs all is not lost, you can use your mk2 beam.
    If for have early NON ABS hubs they will fit straight onto the mk2 beam.
     
    If you have ABS hubs it goes as follows
    Horrible drums
     

     
     
    and off
     

     
    Now when you compare the ABS hub with what you have taken off the problem becomes obvious
     
    Old one

     
    New one with stupid massive abs sensor

     
    The hole in the beam is too small so to get the hub to fit it has to be opened up to 61mm.
     

     
    There are a few ways to do this I used one of these with a carbide tip
     

     
    Hole marked up to be widened
     

     
    And done
     

     
    Then it all fits together
     

     
     
     
    Brake line
     
    If you have mk3 disc setup ones they fit straight on but if you dont you basically have two options.
     
    1- replace the line with some copper or nickel brake line. If you dont have the tools to do this yourself most motor factors will make it up if you give them a length (bending a bit of thick wire into the right shape is a good way to get the right length)
     
    2- bend the old drum pipe to reach the caliper. This works OK but IMO a new pipe is the way to go.
     
    Ill be making up a new pipe for mine but just to prove that the drum one will fit
     

     
     
     
    Handbrake
     
    This has to be done no matter what beam your fitting.
    You will need to get a pair of mk3 cav disc handbrake cables which fit directly onto either beam. The problem is that mk3 cav cables are longer so you need to loose the slack.
     
    The easiest way to do this is to get this little bugger (the adjuster used on both 84-88 mk2s and ALL mk3 cavs)
     

     
    The adjuster is 140mm long overall and by making it shorter you loose the extra slack on the cable. You need to cut a bit out of it (about 25mm) so you end up with it being 115mm long.
    Take the width of your grinding disc into account, it needs to end up being 115mm long or you wont get the ends of the cable into it.
     

     
    And weld it back together
     

     
    This is fitted as it would normally be and the mk3 disc brake cable will now fit the car perfectly. Once its all bolted back up and the system is bled your good to go.
    You can also use larger Vectra or Saab 9-3 rear disc brakes if you want. Its a cheap 5 stud conversion too. Backplate needs redrilling though..
    Edited 7 Aug 2014 by Frisco
  7. This is a basic how-to on removing the internals from an F16/F20 so you can swap the housings over to allow you to keep your F16 housing.
     
    1   Remove the gear selector turret by removing the four 11mm bolts at the base and giving it a tug and a wiggle.
     


     
    Disconnecting the gear linkage can make this easier, if you do this make sure you split as in the pic below not by undoing the bolt on the shaft to save you having to reset the selector.
     

     
    2  Next remove the reverse light switch. This isnt strictly necessary but can make life easier and it just screws out.

     
    3  Undo the ring of 13mm bolts on the end casing of the box. There are two rings of bolts, the inner one is for the 5th gear cover plate and the outer is for the gear cluster. Its the outer one you want. (that blue thing at the bottom is my finger)

     
    Once thats done the gear cluster will simply pull out.

     
    4  Remove both drive shafts. (if your attempting this i take it you know how to remove drive shafts ;D)
     
    5  Now the difficult bit. You need to remove the big diff preload nut (castle nut)  These are set by weight at the factory so you need to mark its position and count the number of turns it takes to remove as it needs to be put back in the same place.
     
    Remove the locator which is a 10mm bolt.
     

     
    Then you need to spin the nut out. Some people use a hammer and chisel but i am not that way inclined so i made this.
     

     
    Which fits like this and allowed the use of a 30mm spanner.
     

     
    Castle nut out. These are bugger tight so have your breakfast before you start.
     

     
    6  Remove the drivers side diff bearing by removing the 5 bolts and prying it out. This takes a lot of prying and some swearing.
     

     
    7  Once you have that off you remove the bottom diff plate (gearbox sump) Have a bucket as there will be oil in it.
     

     
    The diff should fall out now so if the box is still in the car don't have your head under the hole.
     

     
    Thats all of it apart. Both F16 and F20 are the same to dismantle.
    Reassembly is just the reverse except for the diff which is covered below
     
    8 The F20 diff is slightly too wide to fit into the F16 housing and catches on the ends
     

     
    So it get it in the edges of the housing need to be relieved slightly on both sides.


     
    This is done with a sanding disc covered in wax so to stop the dust getting into your gearbox. Give the inside of the box a good clean afterwards, needless to say filings on the inside of the gearbox isn't a good idea.
     
    Pay attention to the setting of the diff preload nut, it doesn't have to be 100% perfect but as close as you can get.
    Replace all seals and gaskets. Refill with good quality 75-80W oil.
    Job done 
     
    Edited 7 Aug 2014 by Frisco

  8. Staples 2 Naples 2006

    · andy · 10/24/15 00:49

    Almost ten years ago now, myself and Dougie (and Dan) took part in a banger rally. We bought a 130 for £100 (well those days are long gone!), and did it up over a couple of months. This trip really set the tone for storming across Europe on a mission, that in part led to us all going on our first EuroTrip as a formal club event in 2009.
    To celebrate, what follows is a re-print of the Total Vauxhall we produced to mark the event with updated insight (random comments based on hazy recollections of the event..). Enjoy!

     

    I shot photos and videos whilst still doing the lions share of the driving with dougie who was writing the whole way. 
    (dan.. well, we love you mate, but dan ate and slept, and did some of the driving..)
     
    Here is the magnificent beast that ended up going to Ireland on a back load..
    I wonder where it is today. It was a great car!
     
     
    _____________________________________________________________________________________________
     


     

    Here you can see some of the challenges, views and the other MK2 we convoyed with.

    At the end of one day (Naples) there was a planned ambush! We knew something was afoot tho,
    and the SRI130's central locking didn't let us down!

    Late night convoys through adn over mountains, with some interesting rest stops! (Also the starting point @staples!)

    To those that donated to cancer research for us - I'm still seriously chuffed today that we raised a grand and had fun doing it.
    I'm proud to know such a cool bunch of people.
    Cancer research might be a 'mainstream' charity, but it's an evil, viscous condition of which my mother died. 
    In many ways, she's the reason I started this website - Cancer Research UK is our charity of choice.
     
    It may be that S2N has gone the way of the dodo.
    Regardless, here's a link to the site on the rally itself: Staples2Naples website.
    Here's a link to it on the wayback machine that should still work: S2N on Wayback
    You can pretty much stop reading here.. but if you really care, you can read the progress diary (cough) from the run up to the event below.
    _____________________________________________________________________________________________
    By means of a bonus. Here is the remnants of our project blog, although I'm unsure where some of the photos went. (I blame dougie for poor photobucket stills)
    Project Blog
    20th June - Dougies got the trackrod ends, now it just needs tracked before the tyres go bald. I can safely conclude that the car is riding much better now not only because we changed the driveshafts (dougie) but because the wheels feel more at one with the road (and society at large) now that we have fitted some new wheel centres that I'd found hiding in my garage!
      Dan also cleaned up Dougies "spare" drivers seat for his red 130, the existing drivers seat had worn through to the wire frame and felt like you were sat on a bench. The new " brown " one not only compliments the rest of the grey blue interior perfectly, but its probably the best of the lot!

    __________________________________________________________________________________________
    14th June - Changing the track rod ends didnt go to plan as we were sent the wrong ones at the weekend! - still we changed the oil for what must have been the first time in years, sorted out 4 matching sets of wheel bolts removing the (VW ones in the process) and I found a set of centre caps I'd been saving in my garage that will fit her! I'll upload a pic for comparison soon!
    _____________________________________________________________________________________________
    8th June - As Dan's Astra needs a clutch, and Dougies GSi has interesting isues Myle is still being driven to Bath and back each day.
    The fact there is creaking and grinding noises from the front end doesn't seem to put you off when needs must! Hopefully the guys will succumb to my nagging about us getting some little jobs on it done, so I can load it up with 200kgs of bits for our stand at billing this year!
    Anyways, I've decided that all teams on a banger rally where people usually paint their cars in horific ways needs a 'great' team logo.. here is why me and photoshop should never the two be paired..
    from left to right:

    Dan (I spent most time on), me (need to find better pic!) Dougie - (with hair!!!)
    Finally, I've ordered the stickers for the rear window and bonnet, which are a modified version of the club keyring I designed. I hope Dougie & Dan can get some decent total vauxhall ones, as well as ones from other sponsors. Time to get the word out about our mission. No pristine low milage Cav GL for us, oh no! A Battered SRi130 is only way to travel!
    _____________________________________________________________________________________________
    29th May - Fitted my mk3 cavs old wheels, got rid of the judder, had a good look round the car, plenty to get done!
    Must add that these pics were taken at lockups, not my house, washing machine or pesky cat gaddamit!!

     
    _____________________________________________________________________________________________
     
    9th May, bought for £100 - has allready had indicators, trim, K&N, and put out a wanted list of a great many parts!


  12. Belgium 2009

    · andy · 10/24/15 00:53



    Images from the article that we took while we were out there are at the bottom of the transcription that follows.

    Two years ago, an article in TV proudly told us "You have to go to Europe next year. Trust us on this — it’s brilliant fun and once you’ve been, you’ll want to go back again and again.." This proved to be a prophecy well worth fulfilling. At Billing for the past couple of years we've been flyered by the Manta club of Hageland in Belgium with a view to us attending their bi-annual Manta and Ascona meeting in Aarschot. We made our final preparations at Billing, even managing to convince another couple of cars from our not insubstantial stand to tag along too. This year, the Belgium event fell on the 24th - 26th of July; just two weeks after the VBOA's annual GM extravaganza. 

    Many of those attending managed to get a few days off work around the said weekend so that we could both extend the convoy on the way to the event and have some recovery time afterwards. With club members coming from as far north as Newcastle, as far west as Somerset (and even Ireland!), Thursday the 23rd was a day of meeting up with all the fun of a convoy until everyone had been collected en route. At the last stop before the run through to Kent, each car was furnished with a walkie-talkie by the club. These proved to be an inspired addition to any convoy. The ability to communicate, organise and mercilessly take the piss out of each other on the fly was fantastic. It was then off to Dover for dinner and beer before the 6am crossing to Dunkerque on the Friday morning. 

    Rain and an orange tinted darkness greeted us from the windows of the Travelodge, but mercifully enough, it soon brightened up. At around five-thirty am, six Mk2 Cavaliers filled with camping gear and bleary-eyed but excitable car nuts boarded the ferry. This was a welcome opportunity for Paul to once again replenish his oil reserves. It was a surprise for everyone to see anything at all on the bottom of his valver's dipstick after the blue plumes and acrid spray we'd been treated to on the way to Dover! He had however come prepared; with about four gallons of Texas gold on board to keep on top of the situation. 

    Once off the ferry, we had to get to grips with driving on the opposite side of the road. Although the majority of us had European driving experience (and the club covering the "Staples to Naples" banger rally in 2006 with TV) nothing really prepares you for crazy priorities at junctions and the French police. Our first planned stop was a much hyped trip via the historic beaches of Dunkerque which seemingly promised to be an epic photo opportunity. After close to an hour of driving, and believing we were nearing our destination, we arrived on a patch of ground next to a river, only to realise we could still the the ferry not too far in the distance! We pressed on, and having finally found a side road allowing us down to the front, we made it to the beaches. Photo opportunities were sadly limited due to various dreary bits of 1970's concrete street furniture, and in modern times these beaches don't really exude the sense of history we may have been expecting. In fact the scene more closely resembled Blackpool seafront than the setting of some of the biggest battles in our history. Our presence had not escaped the attention of the local constabulary either. A marked car was followed by several more discrete offerings from the Gendarme which proceeded to circle the block casting a dark Gaelic shadow over our first stop making us feel particularly welcome. We decided to move on towards Belgium.  

    The run between France and Belgium was punctuated with fuel/call of nature stops, photo and video opportunities and a short but torrential downpour which left us wondering if Jonny had led us back to the channel! Motorway services in Belgium soon dashed any hope of cheaper fuel abroad. At over €1.30 per litre, even allowing for the exchange rate, it was still cheaper back home. The food there left something to be desired too, but hey, neither Belgium nor motorway services were ever known for their culinary delights.

    As we neared the shows' location, we learnt that Jonny's (trust me I'm a lorry driver) directions extended only as far as the nearest motorway exit. Thankfully Ivan's hawk-like vision drew attention to the first of some (tiny) yellow signs on lampposts bearing the word "Manta", and we managed to find the show site. It was around mid afternoon by the time we rolled in, and there were only a few Mantas over in one corner and no Asconas whatsoever - let alone any of the C variety. First impressions ranged  from " Where is everyone? " through to " Is this the right place?! ". Happily though, we were fairly early to arrive in the scheme of things and a steady flow of cars soon began to fill the site.

    Local facilities were good, with two supermarkets within a five minute walk providing well priced food and more importantly; Beer (big shout to the Kaiser Chiefs, you know who you are!). Facilities on the camp site were "limited" with communal toilets!  The seven am toilet visit can be challenging enough for a man without standing two feet from twenty or so women who are queueing for the two available cubicles. And the inmates at Parkhurst would have thought twice about the showers. 

    The weather was more than kind to us. The few brief rain showers we had really did nothing to dampen anyone's spirits and most of the time we were there it was genuinely hot. By the time the site was full, just about every age and model of Manta and Ascona were represented in both standard and modified forms. Engine conversions were not just limited to GM units either. One Manta A in a particularly striking shade of orange had been very neatly equipped with a straight six BMW M3 engine! Other conversions of note were another Manta A with an XE running a sneakily almost hidden supercharger. At least two of the Manta Bs had been beautifully fitted with 24V Carlton GSi motors too. The usual spread of carbs and throttle bodies were also in evidence, most notably in an outstandingly built Ascona A, finished in a rather individual shade of metallic green.

    The majority of Ascona Cs (Mk2 Cavaliers) in attendance were on our stand, particularly in modified form. Many of the cars local to the event had lowered suspension and different wheels, but little in the way of engine mods, largely due to extreme rules imposed in Belgium. Our Mk2 Cavaliers therefore drew a lot of interest, especially with the bonnets up!

    Despite doubting whether Belgium was ready for our little convoy, Leuven was ready for anything. The imposing gothic town hall and surrounding architecture gave little away as to this picturesque town's burgeoning nightlife. Happily our visit also corresponded with some sort of local festival with literally tens of thousands of people cramming the streets to party! This was right up the street of the occupants of our Beer powered support vehicle - the 3.0 Omega Elite driven by Ben Thurston from CJK and Paul from Young's engineering. They may have missed the ferry, the convoy across and most of the show but my god they made up for it in style. 

    At the time of writing it is still uncertain which way the GM board is going to go with it's choice between the Canadian-Russian consortium led by car parts group Magna International and investment group RHJ International. With the former indicating it may well close key European manufacturing locations with the loss of 11,600 jobs. At such a watershed moment over the future of the former GM Europe in general and with the loss of Saab already in the bag it seemed almost pertinent that our Cavalier tour took a detour from our road trip back to port to visit the site that was actually the birthplace of the majority of the Cavaliers in convoy, (the alternative slightly less well bolted together plant of choice was Luton - where all the cars seem slightly more prone to rust from too). From some distance the GM presence looms large, emblazoned on chemical towers and buildings across the industrial landscape. It was impossible not to notice how much one company had impacted a geographic area to such a vast extent.

    After getting the shots that we wanted we found ourselves on six lanes of pristine yet desolate tarmac running from the plant to the edge of the industrial district. We had casually planned a couple of shots of the cars in formation, but of course, owing to being caught up in our little 'pilgrimage' excitement quickly took over again. The resulting 30 seconds of footage more accurately resembling strip action at the Santa Pod. Everything that we had been through over the weekend culminated in that one shot. It felt like the cars were on home turf for the first time in 25 years and eager to please. Until the Luton built Calibre decided to let the side down. Cut to the end of the clip and there is a moment where the V6's torque can clearly be heard pulling the thread from the gearbox mount. Quick thinking and Keir's big hands made light work of swapping out the bolts from Richie's strut brace to get the car home.

    So was it all worth it? In short, a wholehearted YES! Some may doubt that a smaller club with a niche outlook and without the resources of some larger clubs could pull off a jaunt to the continent, but this could not be further from the truth. Booking the ferry in advance and being flexible on your crossing time keeps the cost down. Taking two to a car spreads the fuel costs. Eating locally from supermarkets etc keeps those costs to a minimum too. European mapping on your SatNav (including 'safety' cameras) is a must, and walkie-talkies come highly recommended! Our event provided us with a shared experience that none of us shall forget.

    Perhaps the quote from Dougie's first trip to Belgium does sum it up most effectively;
    "You have to go to Europe next year. Trust us on this — it’s brilliant fun and once you’ve been, you’ll want to go back again and again.."

    We are already planning our next adventure. 


    Images from the article that we took while we were out there. Many of which were not included. Many more exist too!

       

     
      


       


       


       


       


       


       


       


       


       


       


       

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