Just another yellow P5 build...

Hopefully that's true. Having spares doesn't bother me though. If the harness was in better shape/unmodified, I think there would be better odds of that though.
 
I found another diagram that may be some help.

Try to test for +12V at all the terminals on your ECU in all the different ignition positions.

I know my scanner won't connect until I turn the ignition on.

Maybe one of your ignition terminals isn't getting 12V.










 
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That might be interesting. I'll look into it. But when the key is switched to on, all the wires to the ecu that are supposed power up at that time seem to work. My brain! Also went out an hour ago and verified continuity through all the ecu harness ground wires.

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I'm thinking either your ECU isn't "turning on" or it has decided to shut the car down.

I know the car won't be allowed to run if there is no crank signal but that resets every time the key is shut off... Then you get a couples parks then nothing.
I'm pretty sure the fuel pump turns on every time too.

Maybe you can try to find out what conditions will make the ECU kill the engine.
(I know the Google is supposed to be my friend but it really doesn't like me...)
 
Checkpins #71 & #97 specifically to see if they get +12V when the ignition is on.

It's the fact that your scanner won't connect that makes me think your ECU isn't turning on.
 
71 and 97 do both have power when switched to on. As well as 55 & 4 which are on regardless of the ignition. They're to keep the memory for the ecu I suspect.

Checked all grounds too, all are fine.

It's as if the ecu isn't there at all.

I might have a short somewhere that is just frying ecus on contact, but If that's true, I don't know where it would be or how to find it without delooming the whole harness.

But it also seems like a short should have popped the engine fuse, like every one else with this problem.



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It could be an "open" circuit too, where a wire is broken and not conducting. (or even worse,.. a bad connection that's really hard to pinpoint)

You could try unplugging your harness at both ends and check for either a broken or shorted wire.

Is there anyway you can plug your two ECU's into a protg to see if they're blown ??
 
You can maybe try unplugging just the ECU and test the terminals on the harness for resistance for the pairs of wires going to different solenoids and sensors.

Start with the cam and crank sensor wires.

This way your testing the sensor and the full length of the wires.




 
maybe a silly question but i had this when i swapped my engine out. have you checked the plate behind the crank pulley? making sure its straight and the correct one for your sensors?
 
It's the same pulley I was using before, I'll check for damage though. And I'll start pulling plugs and testing, that seems like the next step.

Thanks again everyone, we'll get there.
 
Damn dude! I don't own a p5 (I kinda want one now after seeing what you've done to yours) and I'm in the group pulling for you to get it running (esp. after you getting war wounds). GL sir! You'll get it figured out.

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Damn dude! I don't own a p5 (I kinda want one now after seeing what you've done to yours)...

What are you talking about ??
He Killed His Car !!!
Why would you want a Dead Car ?!
He may only have One option left !!


 
I'm trying to be pragmatic...

Seriously... I hope you get your car running and for shyte sake tell us what got it going if you do.

You can even get a scope and look for stuff like this...





 
I'm trying to be pragmatic...

Seriously... I hope you get your car running and for shyte sake tell us what got it going if you do.

You can even get a scope and look for stuff like this...






it looks like you would have all the answers pcb, if we only new the questions!!!
Great info coming out of this fault.

Maybe a yellow and gold sledge hammer same as the engine should live in the back come how haha.


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I tried to find an output signal for the CKP sensor but none was listed...

It should look something like the ones I posted... I don't know what the scope setting should be.
 

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