1998 Chevy C1500 W/T 4.3L – Recently started intermittent starting. Cranks fine but will not start. New cap, rotor, coil, fuel pump around 2 years old. Crankshaft sensor & main seal just replaced by repair shop that stated there was some error code in the history indicating a failure. If it starts it may run fine for a day or two and then won’t start again for a day or two. Looks like it is getting spark all the way to the plugs, fuel pressure looks good at the rail (around 60 lbs). Even tried starting fluid and still no kick over. When it does start tons of smoke and raw fuel out the exhaust. There is a pattern when it will not start, turn key on and wait for fuel pump to kick off, turn key to crank and you immediately hear a very small/quick stumble then crank and crank. If I release the key and let the fuel pump charge back up and cut off and turn the key to crank again a faint stumble and crank, crank. Over and over this pattern occurs, crank, let go key, wait for pump, turn key, faint stumble, crank & crank, let go… on and on. During that cycle when I let go of the key after cranking and don’t wait for the fuel pump to catch up and cut off but try cranking again quickly I don’t even get a faint stumble, or if I change the position of the throttle also. Any suggestions? I hate to keep throwing money at this, could it point to ignition module, wiring, or some other item? Are there any isolation steps I can perform?
Tags: 1998, 4.3L, C1500, chevy, Intermittent, recently, started, starting, wt