Hi all, i have a 99 sonoma sls 4.3L that wont start, it happened all the sudden, ran fine when i parked it, it is curently winter here and when I parked it we had snow that day which turned to rain overnight, the next day I moved it out off the street in the driveway and it sat till the next morning when I tried to start it, it wouldnt start, would turn over fine, but wouldn't start, it would always chug abit after I let off the key to try and turn it over as if it was trying to start. Then I burned the starter out, got it towed to the shop to get another starter put on, and it started for them in the garage, then for me when i went to pick it up, and twice after that running arrands on my way home, parked it in the driveway until the next day had a snow storm over night and woke up in the morning to a no start, popped the hood to find a couple centimeters of snow. I have spark and I can smell fuel as if its flooded. Any help would be appreciated.
1999 gmc sonoma 4.3L V6 wont start!
- Thread starter Hypnus
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Molson02536
New member
Shot in the dark, but it could be a bad ICM. Remove yours and have it checked at a parts store, most will check it free of charge before you buy a new one. Also it wouldn't hurt to see if it would start with a little spray of starer fluid in to the intake and see if it will start and run.
If it does, then there is a good chance our fuel sending unit is going bad or has a bad ground. Check the fuel pressure at the shredder valve to see if there is 62PSI when you first turn the ignition key without starting it.
Keep us posted
Molson02536
tried quick start fluid and it did backfire and shot flames out the intake but didn't start, and it took alot of turning it over to even get that out of it, for the icm, where is that located?, the truck has new wires, plugs, distributor cab and rotor button, and a new starter, bought a new coil too, but put it on and still nothing.
Molson02536
New member
Recheck your firing order, it sounds like you may have some of the wires crossed from the back fire you mentioned.
As for the ICM, is located towards forward of the engine on the ignition coils. It has the silver heat sink attached to it.
Keep us posted and keep up the good work
Molson02536
ok, so i couldn't figure out what was wrong with it, so i had it towed to a garage again, and they fixed it, saying it was a backed out plug on the hard to reach rear drivers side, the mechanic said he could turn it out with his fingers!!!!, would that have caused it to not start?, what about the other 5 plugs?, i could understand if it ran like shit, but it should have started, he mentioned that, that was the reason it was flooding and gas was in my oil.