Side of road dead. codes 42 36 33 75

1995 RMW: 2 hours into a 3 hour trip, I suddenly lost power and the engine died. Coasted to the shoulder. It was -15°C, windy, snowing. I tried to restart and it cranked, popped occasionally, generally acting like there was no fuel. Pushing the fuel test port Schrader valve, there was some pressure. I could hear the fuel pump run, and it built pressure back up. Checked the HVAC for trouble codes, it showed

42 (Ignition control (IC) circuit: shorted or grounded circuit),
36 (Distrigutor ignition system: faulty high resolution pulse or extra low resolution pulse detected.),
33 (Manifold absolute Pressure (MAP) sensor circuit: signal voltage high- vacuum low), and
75. (Transmission system voltage low)

Tried cranking again, it popped and spat but eventually fired up, and quickly smoothed right out. Full power, like nothing ever happened. As I was closer to my destination than home and it was after midnight, I carried on.

Ran fine for the next hour. Got off the highway, was within a few blocks of my destination and it died again. This time, code 36 popped back up but the other codes had cleared themselves. I put my foot to the floor (to trigger the "flooded engine start" protocol), it started quickly and ran fine the rest of the way.

At this point, I assume the ignition cut out for some reason. Wires and plugs are less than a year old, as is the genuine Delco opti. Coil and IC module are probably original. Don't have any tools with me.

Any thoughts?

What shape is the opti wiring harness in? The clip on the opti end almost always breaks when removed, maybe yours came loose?

Ignition control module. I dealt with the same issue on my 94.

I had the exact same thing happen to a 95 9C1 I had. Car cut off, acted like it was running out of fuel. Would start occasionally run fine and then die. In my case it ended up being a bad optical sensor in the Opti. Check your Opti harness, and replace the ICM and look for arching from the coil. Unfortunately I suspect you will be replacing your Opti. From my experience with these cars it will end up being your ICM or Opti.

I know everyone dreads replacing the Opti. I have done several and can do them now in less then 1 hour. On a side note, if you do go that route...I have heard good things about the $59 dollar units from SkipWhite performance. Look them up and decide for yourself. Good luck...hope she gets you home.

The opti is a new-last-spring Delco with the Mitusbishi sensor. I didn't notice any problem with the clip at the time, I'll check it again though.

I thought maybe a ground, given the wide range of codes that suddenly appeared, but can't find any problems there. Two of the codes are ICM related, so I just ordered a new one and a coil to go with it. Not a definitive diagnosis, but they are original so it can't hurt.