Coils not getting signal??
#1
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So I just finished my harness on my car and we have been working on the car for about 8hours and can not get ANY spark!
We have signal to every sensor, tested 02s, tps, map, iac, injectors, cam sensor, crank sensor etc. All show movement on the startup test.
The coils are getting power to the pink, ran it right to ignition on a 20amp fuse.
I tried my pcm in a running car, no problem, tried his coils still nothing.
We jumpered the Purple wire on coil #1 and it fires.
What would stop the PCM from sending a signal to the coils? VATS is turned off in the tune.
Thanks
Jay
We have signal to every sensor, tested 02s, tps, map, iac, injectors, cam sensor, crank sensor etc. All show movement on the startup test.
The coils are getting power to the pink, ran it right to ignition on a 20amp fuse.
I tried my pcm in a running car, no problem, tried his coils still nothing.
We jumpered the Purple wire on coil #1 and it fires.
What would stop the PCM from sending a signal to the coils? VATS is turned off in the tune.
Thanks
Jay
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The harness is from a 2001 2500 P/U, pcm is a 2000 trans am. We back tracked pretty well every wire to make sure they are right and it seems fine.
Also I tried running constant power to the coils (fused) and cranking it and that wasnt it.
I have basically all my 02's, coils injectors pcm fused to ignition, then the PCM constants are fused to constants.
I did notice while cranking the ignition goes to ZERO so this is when we jumpered it and got nothing.
Im gonna try putting the coils on relays and possibly the injectors (but i know im getting fuel)
Jay
Also I tried running constant power to the coils (fused) and cranking it and that wasnt it.
I have basically all my 02's, coils injectors pcm fused to ignition, then the PCM constants are fused to constants.
I did notice while cranking the ignition goes to ZERO so this is when we jumpered it and got nothing.
Im gonna try putting the coils on relays and possibly the injectors (but i know im getting fuel)
Jay
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If ign goes to zero, does the tach signal go with it?
If so, you'll have a no start condition. You will also have no fuel pump restart.
The PCM MUST see the tach signal....
If the ign loses power when you go to the start position on the key, that will cause what U R describing.
Do you have the neutral sw wired in?
If so, you'll have a no start condition. You will also have no fuel pump restart.
The PCM MUST see the tach signal....
If the ign loses power when you go to the start position on the key, that will cause what U R describing.
Do you have the neutral sw wired in?
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wow so after all that pulling the wiring apart i decide hey lets hook the pcm ignitions to the wire I used on my LT1 and the one that stock motor uses. BAAAM Fired up first turn
God damnit hahaha
Thanks for the help!
Jay
God damnit hahaha
Thanks for the help!
Jay