I think I have either a problem with my ICM or my opti. The issue I have is the car allways starts when cold and will run for awhile and then die with no warning, it runs fine up to the moment it dies. It will start in bursts after that, but will only run normally after it is given time to cool down.

Occasionally it runs fine the other day I had it out for 30 or so minutes with no problem. I managed to test a few things while the car was not starting. Fuel pressure was good 38psi with the Key on. I swapped a different coil in still wouldn't start. I did notice I didn't seem to have a spark at the coil when the car wouldn't start, bright blue spark when it will start.

So my thinking is either my ICM is bad, or I am occasionally not getting the reference signal from the opti. Problem is I seem to have to do all my testing when the car will not start, which only happens sometimes and for a short period of time. Any quick way to isolate the problem? Any other posible causes?

I thought I had this fixed a week or so ago, no such luck.

 

So after doing some searching, I found that I should get between 1 and 4 volts ac at the white wire on the ICM. Can I assume that if I have this signal at the wire and no spark at the coil the ICM is the problem?

 

I just scanned the car got code 36 something about there not having been enough high resolution pulses at least 5 consecutive times.

ICM is $200 here

 

I had the same problems with my 94. I changed the coil and the ignition switch but it didn't help. Finally replaced the Opti and I cured the problem. I took the time to replace the water pump and installed a good set of OTVC wires at the same time. Been running great since.