minnows93

i have a 93 c4 with 65k and recently had some problems. When stopped at a light, my car died but started up right away. Afew days later, the same thing happened only it took 6-7 tries before it started. Then just yesterday while it was parked in driveway, it started right away, and ran for about a minute then died.

I can't get it started at all now. I have some friends that are "car guy's", and they seem to think it is my opti spark. I did some research, and it is not a real cheap fix. I would like to find the problem before buying a new opti. Is there any way to test and see if this is the problem?

If anyone has suggestions, or has had this problem, i would love to hear from you.

Thanks, Matt

81c3

Unless you recently wet your OptiSpark unit, then I wouldnt be so quick to jump to the conclusion that its bad.

It sounds more like the problem could be fuel related. You should check the fuel PSI at the fuel rail before proceeding. Also, check to see that you do have good spark. Pull a plug wire and crank the engine. You should have a good loud snap when the wire is held close to a metal ground.

Theres a host of other problems that can be plaguing your car. Try to get the codes pulled by someone with a scanner, or at a shop, if you can get the car there. It may cost you a little now to get the car to a qualified mechanic, but in the long run, its allot cheaper than throwing parts at it until you find the problem.

Good Luck!

STL94LT1

Any codes?

psychodiagnostik

When the opti on my '93 died (when a coolant hose burst) it would start fine, idle sort of rough, however it wouldn't rev past 2K rpms or so. It didn't trip any codes either, which was weird.

EvanD

Doesn't sound like the opti to me either, maybe the coil or coil wire (high tension lead).

H P Bushrod

I'd go the cheap route first...When was the last time the fuel filter was replaced? Any codes? I wouldn't jump on the opti too quick. Once they die, the car usually doesn't start back up.

EvanD

I don't think it's fuel related since it dies at idle.... If it was he would be complaining at off throttle speeds...

Another possibility would be the plunger in the MAF idle circuit but I would think even with this AFU it would start even though it wouldn't run with his foot off the accelarator.

Still think its electrical and probably the coil or wire.

Lichen

The '93 doesn't have a MAF, it's speed density. I'm with the others. It could be the ICM, but you really need to pull the codes before throwing money at it.

pcolt94

Does not sound like classic opti symptoms. I basically agree with the possibility of the ICM theory based on current information. But I would also so measure fuel pressure to at lease eliminate that possibility. You can also listen for the pump to start every time (2 seconds) the key is turned to the on position.

If the ICM is intermittently defective there is really no code that is going to nail it down in that way. Substitution is the best way to go on that. Check for a good spark off the coil wire if you can catch the problem when happening.

ol school

spray some starter fluid /if it starts you know its not your opti. Probably fuel pump or filter..

alby53

fuel pump

DVNCI

A bad coil can behave like that as well.

runner140*

I went thru a fuel pump/fuel filter with the exact same symptoms.

Mr Mojo

I would also check the coil wire as someone else mentioned.

Mine was rubbing on the water pump and I would have a miss at around 5000 RPM and sometimes a no start condition. It never died at idle though.