RobsWS6

Maybe I missed it but have you checked the fuses? One went on me, same thing. Crank but no fire. Popped in another 10 and off I went.

Just a thought...

ksmyss

i have had this happen to me twice.

the first time it was a bad/cracked coil wire. when it would start it was throwing miss fire codes, so we popped the hood in a dark garage and it looked like the forth of july at the coil wire/opti connection.

the second time it was my ignition control modual. it went out going down the highway. and would fire back up.

StngStlkr

Well I didn't get a lot done today in the way of fixing my car as time was limited. Like I posted earlier I tested the voltage at the harness that plugs into the ICM, it turned out fine. I also attempted to test the coil like it states in the manual. I inserted a small length of metal into each of the top holes(primary resistance I believe?), then I used an ohmeter to try and measure the resistance there with the key on. However, the manual(crappy Haynes) doesn't go into a lot of detail so I'm not sure if I did it correctly. But when I did it there was no reading at all. Like I said I'm not sure if I was performing this test correctly or not, but it was kind of odd to me because all the other tests turned out just like I expected. Also, though I haven't had a chance to test the fuel pump pressure I have a feeling that this isn't the problem. I can hear it prime like normal everytime I turn the key, and when my first fuel pump went out it acted totally different than this. Also, what is the easiest way to test spark at the coil? Hook up a spark plug to the coil wire and ground it? Hopefully tomorrow I can get more done on this problem.

Smokn '94 Z

The esiest way to check to see if the coil is working is to take the coil wire off the opti end & hold it agains the block with some rubber gripped pliers. (linemens) It is an old way of doing things so DON"T GET SHOCKED!!! And if you smell gas or even think fumes may be around then don't attempt at all. Mine did the same thing as yours & I happend to have a spare coil lying around & poof!!!! The car started right up...

Good Luck.

Wild1

Your ignition system may be fine... just squirt some starter fluid in the intake and see if it catches.

Analyze before Diagnosing. If it fires up with starter fluid, then all of your diagnosing of individual components would have been a waste of time. Keep it simple.

StngStlkr

One final update before I leave this topic for the night. I was able to test for spark at the coil, and there was none. So no spark is getting from the coil/ICM to the opti. And from my earlier tests I'm pretty confident that the correct signal is getting from the opti to the PCM, and from the PCM to the ICM. But somewhere between the harness of the ICM and the top of the opti the signal/spark is lost. So tomorrow I'm going to throw in a new coil, and hopefully that will fix it. I'll let ya guys know, thanks for all the replies.

StngStlkr

Ok, I got the car running this AM. Turned out to be a shot coil. Threw a new one, and it fired right up. Hopefully someone can read this, and determine what their problem is.

Smokn '94 Z

I had a feeling that was the issue. I had the exact symptoms last fall when I tried starting it before I went to the track.

StngStlkr

Smokn, your post actually reaffirmed what I had begun to believe was the problem. Once I knew the opti was sending the correct signal, but there was no spark from the coil, I knew it was either the ICM or coil. My first thought was that the coil was more apt to fail than the ICM, and being that you had a 1994 Z28 with the same symptoms, I was leaning towards the conclusion that it was my coil as well. Thanks for all the input though fellas, great to have a resource like this.