1995 GMC Sierra Starting problems

BVALOIS67

MEMBER
1995 GMC SIERRA
V8
4WD
AUTOMATIC
111 MILES

I recently purchased a 1995 gmc sierra 2500 4wd. The truck has about 111k on it. The truck sat for a few months before I bought it but would start right up and ran fairly well. Recently it has not been kicking over, it will crank and sometimes fire with the throttle all the way open, but will not run. I removed spark plug which seemed to be fouled and cranked it w/o spark plugs, noticed a large amount of fuel coming out of the number 7 cylinder. Replaced plugs, it started and ran rough but seem to foul the plug again. Also seemed to be more white smoke than before. Also changed the oil and has some gas odor to it but could have come from cranking and not firing. Any thoughts on where to go from here. Thanks

1 Reply

RASMATAZ

MECHANIC
75,992 POSTS

Next time it refuses to start don't wait for it to make up its mind-do below immediately to determine if its fuel or spark problem

Get a helper disconnect a sparkplug wire or 2 and ground it to the engine atleast 3/16 away from ground-have helper crank engine over-do you have a snapping blue spark? If so-you have a fuel related problem, Do you hear the fuel pump come On when you turn key on? If not check fuel pump fuse and fuel pump relay if okay-check the fuel pressure to rule out the fuel filter/fuel pump/pressure regulator and listen to the injector/s are they pulsing or hook up a noid light. No snapping blue spark continue to troubleshoot the ignition system-power input to the coil/coil packs, coil's resistances, cap and rotor, distributor pick-up coil, ignition control module, cam and crank sensors and computer Note: If it doesn't apply disregard it and keep testing