I have an 89 s15 jimmy 4x4 with a 4.3 that I have been driving for the last month. It hasn't given me any troubles till now. On Sat I drove it out camping (about 1 hour away) and turned the truck off for a few minutes. Went to start it and it would crank but not fire at all. Let it sit for a couple hours and it started fine. Started it/drove it maybe 10 more times the next day just fine. Monday morning started up fine again. Went to leave and it would just crank and crank but not fire. Thought it might be the fuel pump, but I can hear it priming when you turn the car on (tank is full). Tried pouring some gas in and still wouldn't fire or even close to it. Took a spark plug and am not getting any spark when grounded off either directly the coil or dist. Replaced the coil which turned out to not be the problem. Tried doing some of the testing in the haynes manual but it's pretty vague. I don't know enough about these things to try and find the problem. Was going to replace the ignition module or even the hole dizzy. Anybody have any other ideas that I can check on first? Thanks

Jason

 

Changed the distributor out and she runs again.

 

Glad you found the problem.
I was going to suggest the ICM. Although its about the same as a new distributor.