Got Fuel and Spark but no run?!?!

[Jeff]

1990 3.1 car. Drove 20 minutes the other day, parked car. Come out 10 minutes later and car will not fire. Drag it home, got spark, got fuel pressure (over 40) but will not run. Threw a CPS in it yesterday and still wouldn't start. Shot some carb cleaner in it and it fires back to life and runs for 15 minutes, till i tuned it off a few times and the third time I try to restart it, it idles real high for a minutes then dies like someone turned the key off. Won't restart. Once again I check it and it has fuel and fire but won't run. It would run on carb clean but that was it. Come out this morning and crank it and with some throttle it fires back to life and idles fine. So this is telling me something is getting hot and it won't run. I'm thinking ICM but even when it won't run it has spark. Can the ICM shut injector pulse off?? Any ideas?

[3X00-Modified]

The ICM could get hot and screw up but it sound more like your having an issue with the injectors not firing when hot since it ran on carb cleaner.

Try unplugging the ONE injector that is visible on the front of the engine... Oddly enough that is one that went bad on someone at Bfest and prevented the car from starting, as well as another car that I had to diagnose with the same issues... One injector fault on the front bank kills the whole front bank so only three injectors are firing... no where near enough to start it.

[Jeff]

OK I will give it a shot. Just doesn't seem like a ICM to me since it still has spark when it won't run.

[3X00-Modified]

yeah thats why I suggest to try that injector first.

[berettaboi]

yeah for sure a fuel issue if you are getting it going on "another fuel source". the ICM and/coils normally start giving you driveability issues first when they get hot, they begin to miss when over a certain throttle position, usually starts near 1/2-1/3 throttle, and bogs with any input beyond.

[ronaconda]

One bad injector kills ALL injectors not just the front or back bank, at least that was my experience. Pull the upper plenum and test the resistance on all of your injectors.

[3X00-Modified]

You can pull the plug on the rear of the intake and just ohm the two banks and see which one is bad. That's how we found it at Bfest this year and oddly enough it was the front injector you could unplug without taking anything off.

[ronaconda]

You can pull the plug on the rear of the intake and just ohm the two banks and see which one is bad. That's how we found it at Bfest this year and oddly enough it was the front injector you could unplug without taking anything off.

Gotcha...i see what you're saying...

[Blacklit]

need to try this on my indy cuz i have the same issue. finally thought it was road ready, then it started this crap. itll run totally 100% until i turn the car off. try to start it a few mins later and it wont start until its cooled back down again completely.

[Money pit Beretta]

What's that I smell? A sticky for "hot starting problem"?

[3X00-Modified]

smells like burning electronics in here..

[Money pit Beretta]

That freaken stinks.

[Jeff]

Ok you guys rock. After changing the cps and the icm, checking wiring over and over, we got it hot till a no start condition and found the problem. Unplugged the injector harness and found a open circuit on the front bank. What do u know it was the one u could get to also! Off to the parts house and $60 and another hour later I had it fixed! Thanks again guys.

[3X00-Modified]

That’s three now that I know about where that injector has failed... I'm just in awe about it.