Sorry this is a bit long but just wanted to get out what I've already done or checked.

I have a 96 Camaro RS with 3800 V6 and 5 speed. Its basically stock with a cold air intake filter and true dual exhaust. Here's the problem: It RANDOMLY has a fit and wont start, the engine turns over but won't start, won't even hit & miss. I checked power to the ICM, checked ground circuit on the ICM, checked the crank sensor pulse (both sides) to the ICM and they were all good. I had the ICM check twice and it passed both times. I finally found a crack on one of the coils thinking water may have been getting in so I replaced all 3. it cranked and ran fine . . . for a while, then wouldn't crank again. I got a spark checker and hooked it to the plug wire and tried to crank it, it fired right up. This same "cranks, won't crank" has been going on for about 3 months. It will happen when it's hot or cold first thing in the morning, whenever and where ever. The last few times its done it I would stick my finger down by the crank sensor and wiggle the harness, then it would crank. I noticed there would be water/coolant on my finger afterwards. I traced this to the plastic 90 going from the intake over to the tensioner bracket, so I replaced it. everything "seemed fine" till the next morning. I cranked it up, went to the store to get gas, cranked it up again, went back home, cut it off and cranked it one more time then shut it off. About 30 minutes later I went to leave in it and it wouldn't crank, even after wiggling the sensor harness but it was acting like it was trying to hit. I left in my truck and when I came back about 2 hours later it cranked just fine. This has gotten really aggravating because it happens at no particular moment, under no particular circumstances. Does anybody have any ideas or solutions to what the problem could be? HELP!

 

it would help if you have access to a good scanner that lets you see what the sensors are doing when engine is running and/or not willing to run. have you had the computer scanned to see if any trouble codes have been stored in it?

 

I had the same basic problem on my 96 3800, it turned out to be a key switch replacement. The wire in the tilt wheel to the key switch was broken! I picked up a switch from GM dealer and a computer diagram of all components in the steering wheel and replaced it, starts every time!

 

I just had the check engine light checked, it was to do with the O2 sensors. I need to get me a scanner, would be nice and helpful.

 

Are you talking about for the VATS? I tried bypassing the key once when it wouldn't crank, thinking the key was bad but even bypassing it with the correct resistors it still wouldn't crank.

 

there are two parts to the vats system. key/ohm part and bcm/vats module part. test fuel pressure just to be sure its ok. pick up a injector noid light and when i wont start test to see if injectors are being told to fire. or when it wont start hit it with some starting fluid, if it starts and dies or tries to start its a fuel issue. need to make sure it a spark or fuel issue or both. it does sound like a electrical issue but always best to check and track.

 

When it's "not starting" I've put a spark checker on one of the plug wires and it's not sparking BUT at any given moment it may spark & start right up! its just weird like a loose connection somewhere. The guy I got it from had put a new fuel pump in it and I pulled the tank to try to fix the fuel gauge and it does look as if it has been replaced.

 

bummer,,, the only time you can track it is when it wont run and that is most likely when you dont have the tools to do it. better start packin.

 

I got in it today and it fired right up, no hesitation. Could it be getting too much fuel due to my O2 sensors not being in the pipes? but that wouldn't explain the random "no spark".

 

sure sounds like a icm failing. could be like was said and be a short in the ignition switch wiring. if it would just fail it would make things easier.