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Discussion Starter · #1 ·
Back again. 82 P type. Manual Trans.

Tried firing the vehicle up after head gasket replacement and have no spark from the coil/ignitor.

I initially put the distributor in by eyeballing cyl 1 while vehicle timing marks were set to TDC. I now see there is a procedure involving lining up a screw and mark on the distributor, I'll try that this evening when I get home from work, but would that cause me to have no spark at all from the coil?

I checked that I have good output from a test light on the brown 12v wire to the ignitor (left my DMM at work, but bright light tells me good voltage/current flow), and it looks like the ground wire off the ignitor is grounded by the PCM, running through the interior fuse box by driver's kick panel. I didn't diagnose anything in there because I haven't touched any of that.

Grounds I touched look like Engine to firewall, Battery to body, Injector harness to manifold, and one that's by the fuse panel (white and black wire) that goes to body. That ground's bolt broke off when I was trying to clean things up so I relocated it to clean metal and it tests as a good ground.

Only other thing I touched was the MAIN 1 relay. Removed that while cranking to get oil flowing around before I tried my initial start. I do notice with key on, engine off that both the MAIN and EFI relays get pretty hot. Might be normal, just an observation.

I doubt it's the ignitor or coil, car ran just fine (minus bad head gasket) a few months ago. It's got to be something electrical, or if the distributor being off can somehow cause a no spark. I would think it would spark, just out of time if I screwed the dizzy timing up.

Thanks again guys.
 

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Dist off??

Check EFI fuse under the hood??

Reset Power circuit breaker in drivers foot well??
 

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Discussion Starter · #3 ·
AJ
I'll check the distributor, would it cause absolutely no spark out of the coil or would the timing of it just be off?
EFI fuse ok. Main relays click and carry power all the way to igniter.
Care to tell me more about power circuit breaker? Don't know what that is.
 

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If you have an owners manual check the Power CB it might be for ignition, cant remember off hand
 

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Discussion Starter · #5 ·
Update.

Properly set timing and everything is going great.

I'm still not 100% convinced that the distributor being a few teeth off would cause no spark at all. Again, I was testing straight from the stud on the coil and had zero spark. Doesn't look like the ignitor has any inputs besides main relay power and then the pick up signal from the distributor. If anything, it should fire and just be completely out of time. I'm guessing in the head replacement I moved some broken wires around and in my diag moved them around enough that my circuits are sort of good enough. I'm expecting to run into issues moving forward.

Now to deal with the occasional misfire that wasn't there before the overheat event. I was hoping that was all the warped head. Looks like there's more.
 

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In 82, the igniter was trigger'd by the dizzy directly. There is a 2 pin connector between the dizzy and the ignitor. Even if misaligned, as you say, it should have still sparked.
 

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The igniter grounds to the body. With IGN on there is +12VDc to the positive terminal of the primary coil, but no ground. When the distributor pickup coils make contact, they send power (not sure how much, on later models it’s +5V) to a transistor that closes the primary coil circuit just for a split second. This movement of charge induces the spark into the secondary coil (spark to distributor)
 
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