1987 3.2 Carrera Backdate project - Sladeys hotrod

[Bruce M]

OK I’ve tried that now

I first did the tests on the DME relay and they seem to be working fine - pin 87 is charged up with 12 volts.

Then I went to do your test on the injector plug. Tested the first pin and got 12 volts. tested the second pin and got 12 volts again! Not sure what that means.

I tried it on injector 4 and then did the same on injector 1 with the same result


Sent from my iPad using Tapatalk Pro

Good, DME stage 1 is working & if you can hear the pump run during cranking (not just the priming pulse at key on - which confirms stage 2 of DME is working ) then the ECU can see the engine is turning via the crank / cam sensors so happy to trigger the pump.

One of the injector pins should pulse an earth “signal” when the engine is cranking. That will be the grey wire at the plug, if you can see the colour coding. The red wire will stay 12v solid. If you connect the multimeter between the two pins it will read 0V (since they are both at 12v there is no difference between them), when cranking the grey wire should pulse 0v to drive the injector & you should see a voltage reading when measuring between the pins. But it will only happen during cranking & if the ECU is “happy”

[sladey]

Well that was a bit of a saga


Having lunch now but I now have good access to the plug and the socket

[Gary71]

What a ballache.
It will be something small and insignificant, just hard finding the damn thing!!
Good luck

[sladey]

Thanks Gary.

OK I got to look properly at the plug and the socket. Fortunately/unfortunately both are perfect


I took them both apart took out the connectors and wiggled them about and they are all solid as a rock.

Well I’ll just pop it all back in now……


Sent from my iPad using Tapatalk Pro

[Gary71]

Damn. I was thinking it was one of those multipin modern connectors rather than that chunky old school indestructible one!

[sladey]

Yep I reckon I could have lifted the car with it!

Anyway back to re-inserting the intakes and then resumption of diagnostics.

I may end up calling the AA again…..


Sent from my iPad using Tapatalk Pro

[rhd racer]

Ah well - if you don’t eliminate these things then they forever play on your mind


Sent from my iPhone using Tapatalk

[sladey]

Yes that’s very true


Sent from my iPad using Tapatalk Pro

[sladey]

Ok all back in now and I’m in the same position I was in this morning except that I know the main injector loom plug is fine

So here is what I’m getting

https://youtu.be/qLAl7BS0jPU?si=GETxHaW7QblTy_sD

[Gary71]

Is the fuel pump still running whilst cranking?
Can hear it ignition on, but not when the starter is going.

[Gary71]

On my car there is a separate feed to the CDI box that powers it whilst cranking from the ‘start’ position of the key, then it switches to the always on in the ‘run’ position.
It manifested itself as it would cough as you backed the key from start, but not long enough to actually start it.

Could there be something similar on your car? In that the ECU isn’t being powered whilst cranking?

[Nine One One]

Just thinking out loud here, I see in the pictures you have a TOAD alarm, so is the immobiliser shot, or not actually working, or did you remove all that gubbins in the rebuild process?

[Gary71]

Just throwing ideas out there…

What actually makes the spark on your car? I know you have the CANEM ecu for the fuel but where does the spark come from?

[sladey]

Is the fuel pump still running whilst cranking?
Can hear it ignition on, but not when the starter is going.

My hearing’s not great so I can’t be sure. There was pressure in the fuel system but I guess that could have come from the priming. The DME relay also controls the fuel pump. I tested that and I believe it is powering the fuel pump. I also swapped it out for a newer one (can’t remember if it was new or not) and got no change so I’ve swapped it back to the original one.


Sent from my iPad using Tapatalk Pro

[sladey]

Just thinking out loud here, I see in the pictures you have a TOAD alarm, so is the immobiliser shot, or not actually working, or did you remove all that gubbins in the rebuild process?

Although the toad is quite old it’s always worked well - it disarms and arms fine. I had it installed about 15 years ago


Sent from my iPad using Tapatalk Pro