Just bought MK1 Caddy project with MK2 GTI PB engine installed, a few questions

Discussion in '8-valve' started by Josh Slade, Apr 27, 2021.

  1. Josh Slade New Member

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    https://imgur.com/a/p0qEIwX

    coil is wired up like this, positive is right hand side incase you can’t see, there’s an earth from the head going to the ecu (brown/black), still no spark, there’s a disconnect small solid blue wire by the battery, what could that be?

    disregard last two photos i thought they were coming from the ecu, just to check where does the ecu get power from, what wires for power should be going to and from it ?
     
    Last edited: Apr 29, 2021
  2. rubjonny

    rubjonny Administrator Staff Member Admin

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    yep looks good, black wires to coil positive/15 and red/black to negative/1 on coil.

    you should have 2 wires from ecu loom to battery negative as well as one from ecu to head. think i can see them branching off to the left in that pic, where the coil wiring is coming out the ecu loom
     
  3. Josh Slade New Member

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    All the ecu earths seems to be correct, where should it be getting + from?

    Everything seems to be wired up correct, perhaps the ECU is dead, is there any way to test this?
     
    Last edited: Apr 29, 2021
  4. Josh Slade New Member

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    so here's what i can deduce so far:

    Car cranks over from key fine and i get some lights on dash
    ECU is getting power from green plug on back of fuse box, and the relay clicks when i turn key, also idle control valve hums/vibrates
    Ignition control module is definitely wired correctly, relevant wires going to coil, green to ecu and long earth to battery
    I will double check all ECU earths later but i'm sure they're correct

    Still no spark at all

    When i took delivery of the car, the ECU was in the trough where the wiper motor is, and i'm assuming the car had been left outside for quite a long time, so potentially water damaged ECU and ICM

    Perhaps I need to try a new ECU? I'm guessing they're mapped differently depending what car they're from, mine's a TA or TAN ecu, are the other manufacturer ECU's plug and play?
     
  5. rubjonny

    rubjonny Administrator Staff Member Admin

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    in my signature link look for g2pbfull.pdf, that'll cover the ecu but its ce2 fusebox. you can also look at jettya89.pdf that is for ce1 fusebox and also covers the digi ecu, use the one NOT labelled as california and ignore the lambda sensor wiring as you dont have one.

    check the fuel relay, does it click on and off ignition on or just click on? can also measure voltage at the fuel rail with ignition on this should NOT have voltage across the 2 pins

    since isv buzzes this suggests ecu is at least partially working, no spark may be down to hall sensor in distributor or bad ignition components. the coil looks to be a cheap brand, make sure its correct electronic ignition type. or just buy a new mk2 golf bosch one off ebay theres loads on there for around £50
     
  6. Josh Slade New Member

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    I'll go through the wiring diagram and make sure everythings in place. fuel relay clicks on and off after maybe 1-2 seconds, the fuel pump on the car isn't installed yet so, need to install an electric pump so just trying to get it to burst into life with starter fluid atm, ill try another working coil, and get a new hall sensor, could you point me in the right direction to the correct one?
     
  7. rubjonny

    rubjonny Administrator Staff Member Admin

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    if you have a random dizzy lying around you can plug it into the loom and spin by hand. you should see a spark plus fuel relay should click on
     
  8. Josh Slade New Member

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    I'll borrow a dizzy off someone and check
     
  9. Josh Slade New Member

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    Couldn't source an old dizzy, is there anything else i could try to narrow down the problem? Was going to try a new dizzy+hall sender, after that it might have to be a new ECU maybe?
     
  10. rubjonny

    rubjonny Administrator Staff Member Admin

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    dizzy can be from just about anything, even a 1.3/1.4 golf or polo one will do for testing. if you get a new one plug it in first and see if it does anything before going to the effor of swapping. can always return it then
     
  11. Josh Slade New Member

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    I've ordered a new one that comes with a hall sender as the old one was very grubby anyway so will test that when it gets here. if not i can't see it being anything other than a damaged ECU
     
  12. Josh Slade New Member

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    Just tried brand new dizzy and hall sensor and a working coil from my other car... still no spark at all. really running out of ideas here. I can't see anything at all that's out of place. I'm gonna try a new ignition control module, and I may pull everything out and try re wire it and clean all connectors etc before resorting to trying a new ecu. really running out of ideas here.
     
    Last edited: May 5, 2021
  13. Josh Slade New Member

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    ECU and igniton control module are both getting 12 volts, just ordered a new ignition module so will try that next, if it still doesn't work it's going to have to be a new ECU [xxx]
     

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