Intermittent spark/fueling issue, 1992 SE

[zuper8]

All right, I was going to try and figure this out myself, but after lots of farting around with this I am caving and asking for help. This is on my new 1992 SE project, 106k and has been sitting for the past several years. Magnavox ignition.

Condition #1: Will crank like crazy but not fire. Confirmed no spark on any cylinders when it's doing this.

Condition #2: Will sometimes start, and when it does it will run great for a few minutes, then shut off. For every subsequent re-start, it will be harder to start and run for less time, until it returns back to the crank no spark condition. When it wants to stall, I can keep it running if I put my foot on the gas, but as soon as I let off it will die.

Parts replaced/things done:
- fuel pump and fuel filter (previous owner DIY, so can't confirm)
- pulled battery cable boots and cleaned (me)
- tightened loose ICM bolts (me)

I have 92 FSMs, and have been trying to follow the diagnostic procedures, but it's a little bit confusing to me because there are two separate charts for "crank no start" and "starts but stalls". So I'm just getting a little bit mixed up with how to tackle this. So far, my strategy has been to go in order on the diagnostic charts much as I can, and focus on common factors between the two charts, which are ICM and PCM. I realize it's possible that I have a compound spark AND fuel issue, but I'm suspicious that all of this is related. I just can't quite connect it together.

Another important note is that since the car has been sitting, it almost certainly has old gas, which could account for some of the apparent fueling issue. Confirming that the fuel is not bad is also at the top of the diagnostic chart for good reason. However, that doesn't explain the random no spark issue. Any thoughts welcome. I know that the 1995s were the ones that were notorious for eating pcms, but should I suspect that on a 1992?

[harofreak00]

crank sensor

[phils97bonn]

Sorry for the late reply - I've been busy. Check your electrical connections to your coils (clean contacts underneath, and spark plug wires.
Weak CPS (crankshaft position sensor) can cause ignition problems too.
Curious, do you still own the car? lol

[zuper8]

Sorry for being MIA, thank you for the responses! I was getting an error message for several weeks when I tried to post.

Today I swapped out the old Magnavox ignition system for a Delphi setup. Cleaned the ICM grounds very thoroughly while I was in there. It started right up, and this time it ran beautifully for 30 minutes before it stalled and then started to decline into condition #2 as described above. I'm reading in my FSM about module mode ignition and I think that's what's happening when it behaves this way,

However, I did receive a gift after it started having difficulty running today- I finally got an SES light. Code 17 (spark reference circuit) and 26 (QDM fault). It looks like I have PCM wiring to check out. These 92s weren't known for eating PCMs, were they? I had always associated that with the 95s.

[95naSTA]

For that code 17, others were suggesting either the cam position sensor magnet falling out, cam position sensor or harness between the crank and cam sensors:
http://www.pontiacbonnevilleclub.com/fo ... 40035.html