94 GMC Sierra 4.3L stalling problem

NEEDAS

MEMBER
1994 GMC C1500
6 CYL
4WD
MANUAL
310,000 MILES

I have a 94 Gmc Sierra 4.3L that stalls sparadicolly. When it stalls the check engine light comes on and the gas gauge goes haywire, then it stalls immediately. Sometimes it will start right back up, but more often than not, it will take a few hours before it will start again. The engine runs fine when it is running. We have replaced the fuel pump, fuel pump relay, ignition control module, ignition switch, and fixed all ground straps and ground wires to the fuel system. We are at a loss as to what we should replace next, can you help?

1 Reply

RASMATAZ

MECHANIC
75,992 POSTS

Sometimes it will start right back up, but more often than not, it will take a few hours before it will start again

Pull the code/s from the computer by jumping A to B on the diagnostic link connector

Redo below

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 so, 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