I've got a 97 GMC Jimmy 4.3 that will not start. The compression is good, it has fuel, the timing is set, but it has no spark getting to the wires. I have replaced the crank sensor, cam sensor, ignition module, cap and rotor. The distributor is getting juice, and the rotor will turn when you crank its just not getting any fire to the plugs. I pulled a wire off at the plug to test it and got nothing. My buddy has a Blazer that's the same year so we pulled the distributor out of his and tried it in mine, but still no luck. We put my distributor in his to test it and it started and ran fine. I have checked all the fuses in the panel on the driver side and they were all good. Is there another fuse or relay that I could be missing that would cause this? I am stumped with this and could use some advice on where to go from here.

 

Are you installing the distributor properly? EDI Engine Timing

These other tech articles may be of some use to you as well:
Engine Cranks But Does Not Run
No-Start - Engine Cranks OK - Ignition System Diagnosis

 

Yes the distributor is installed correctly. I've checked all the wires and none of them are broken or damaged. Everything should be in working order but I'm just not getting any spark to the plugs. It doesn't make since. The only other thing I can think of would the ECM. Is there anyway to rule it out before I buy one? Could I take the one out of my buddies Blazer and try it in mine? Would it at least let me know if that's the problem? I'm not getting any codes, and the check engine light isn't on. It was running fine one day and wouldn't start the next. It wasn't missing or anything beforehand it ran fine, but now it just won't start.

 

Anybody got any ideas? This thing still has me stumped.

 

What were the results of the diagnostic procedures I linked to above?