last week I installed shorty headers. Everything seemed to be running fine...today I left for work and got 2 miles from my house before the engine died. It just stalled heading up this one hill. The starter cranks but it won't start. Using my ultra scientific test, I'm getting fuel (pushed in the shrader valve, got gas all over me ). Using the "screwdriver test", it looks like I'm getting no spark from the coil. In the fuse box thang under the hood, the fuse labeled "ignition" doesn't seem to be blown, but it has a lil blackness in it. I put in a new fuse and it still won't start.

Any ideas? I'm thinkin either the coil, or some wiring running to the coil that got burnt or somethin along those lines...anything else it could be? I swear, I have my car running about 3 weeks out of every year

 

Check to make sure the coil is receiving battery voltage with the ignition key on, engine not running. Check the coil by using the ohmmeter`s low scale, hook up the ohmmeter leads to the primary terminals on the coil. One in the top left plugin and the other in the top right plugin. The ohmmeter should indicate a very low resistance value. If it doesn`t replace the coil.

 

thanks, I actually did some more searching today and found the info on shoebox's page to check the opti signals, and those are fine, I replaced the coil for the hell of it with a spare I had in my garage, and that did nothing...I'm pretty sure it's the ICM, so I guess I'm headin to autozone after work tomorrow...oh well, I'd rather spend $75 and do 10 minutes work, than have to pay for and replace an opti...

 

ICM?

Is that the ignition module, located just below the coil?
Same problem happened to me, dealer charged me 200.00 to get it fixed...Now I know better, I know where it is, I'll know how to fix it.

 

yeah, ICM = ignition control module. Does my diagnosis sound right? I did the procedure on shoebox's page, pins A and D are getting 10-11VDC with the ignition on, and pin B is getting ~3VAC with the engine cranking. Replaced the coil and it did nothing. So the right signals are getting to the ICM, but the coil isn't firing, but the coil is apparently fine...sound like the ICM is a pretty sure bet? Someone lemme know by 2ish so I don't waste money on the wrong part .

Welp, it's off to work now...

 

ICM is much cheaper than the opti. I wish I had better advice, but when my opti went it was very much the same as you, it just died, while I was driving.

 

had the same problem on my 95 , quit after a few miles found popped ign. fuse . put in new fuse ,turned over revved her up , and it quit again. replaced part# 10483139 and alls well again !!!
also get gm part # 12377900 (gm dielectric grease) not enough comes with the module ( also great for plug & coil wires) only a couple $$$ extra

 

ok, bought a new ICM, hooked it up, everything's fine now...thanks y'all

 

Wow, someone actually fixed their car. Seems like everyone has problems and never gets them corrected. Glad replacing the module fixed you up.

 

Hey that's cool!!! It suuuure is nice to have someone get their problem fixed!

 

Wow, someone actually fixed their car. Seems like everyone has problems and never gets them corrected. Glad replacing the module fixed you up.
Hey shoebox, man youve helped me fix our 94 Z more times than I can count!

 

oh btw, if it happens again, shouldn't be a biggie...the autozone replacement has a lifetime warranty