theplanepilot

My 1992 base coupe shuts off as if you turned the key off about 8 miles into my drive to work every morning. If you try to crank it it turns over great but, will not start. I let it set for 5-7 minutes and it starts right up with a check engine light but runs great and I drive another 20 miles no issues. When I turn the key off and immediately restart the engine the check engine light goes out and I cannot retrieve a code??? 10 hours later I leave work and I drive about 8 miles and same thing. Every day I I have driven it for the past 6 weeks Mon-friday. Any suggestions? it has 102k and I drive it daily. As I approached 100k I took a proactive approach and during the past 24 months I have changed Optispark, wires, plugs, u joints, alternator, water pump etc. nothing has been touched past 6 mos just driven. I have read everything I can on blogs/sites and I am leaning towards ECM. I find all kinds of them that are #16159278 but, mine says 88999183 and it seems to be a tad harder to find. Am I heading the right direction? Anyone ever have this issue???? signed... missing my 1971 :-)

antfarmer2

Try putting a cold pack on the ECM and see what it does. Look at the connections on the temp sensor on the water pump and make sure the coolant is burped and full.

Silver96ce

Why don't you try pulling the codes when it shuts off and before the check engine light comes on during your ride to work? Just leave early or take the run on your day off and pull the code(s).

theplanepilot

I will do the cold pack tomorrow. (Pouring rain now) Car runs great Temps and has no misses. I will check the coolant and burp as well as check the temp sensor and get back to you. If cold pack affects it what does that mean??? ECM? Thanks

93Rubie

At least the issue is consistent. I would take a spark checker with you when this happens and maybe a fuel pressure gauge. It might take 10 minutes to check those road side when the car dies and does not restart.

Your going to have to diagnosis this issue or throw money at it, up to you. Thinking its the ECM and knowing its the ECM are two entirely different things. If you have not already done so, invest in some tools and a FSM or find a competent technician.

Cliff Harris

Usually this type of heat related issue is caused by an iffy ignition module.

Another possibility is that the coil is overheating.

A friend of mine fixed a similar problem by soldering the coil connections.

kimmer

I know you changed the opti but my car acted very much the same and it was my opti. They are also affected by heat.

1stVetteFinally

Yes, ECM rebuilds cost about $200. I used http://www.siaelec.com/ ECM rebuilding services, no issues in over a year.

theplanepilot

I have witnessed 2 optisparks go bad. 1 on my car and 1 on a friend's and both backfired 1 time and never cranked again.

1stVetteFinally

And a cold pack on the ECM wouldn't have allowed those car to start, like it will if there is an ECM problem. If the car starts after being cooled, you have an ECM problem.

vetteLT193

Watch your coolant temp like a hawk. Specifically 160 degrees. If your issue happens around that temperature consistently then your ECM is likely dead.