2004, 4.3 Misfire

[frank3]

2004 Chevrolet 1/2 ton, 5 speed, 4.3. Has ramdon misfire. Have replaced: plugs, wires, cap, rotor, mass air flow sensor, throttle position sensor, fuel pressure regulator, coil, ignition control module and resealed intake and cleaned injectors. Have heard distributor on previous years had vent screen that would clog and cause build of moisture causing misfire. Could this be the same problem with my 2004?

[zibzer]

i cant help but had the same issue with my truck for 6 months. every couple weeks the random misfire would show up and id clear the code. after 6 months it mysteriously never came back. that was 2 years ago. oh and my waterpump leaked for a weekend and never leaked a drop after lol. i love how my truck fixes its own problems

[frank3]

Over the week end, I removed the screen in the bottom of my distributer and replaced the cap and potor. runs great now. Next step, if problem returns, will be to pull distributer, replace "O" ring seal on distributer shaft and insulate the AC hose running along over the top of the distributer.

[oldmann]

My 99 had an AC line over the district. And sour drip water on it and misfire. They put some insulating tube foam over it and no more probs.

[astros_fan]

2004 Chevrolet 1/2 ton, 5 speed, 4.3. Has ramdon misfire. Have replaced: plugs, wires, cap, rotor, mass air flow sensor, throttle position sensor, fuel pressure regulator, coil, ignition control module and resealed intake and cleaned injectors. Have heard distributor on previous years had vent screen that would clog and cause build of moisture causing misfire. Could this be the same problem with my 2004?

 

 

I had the same problem with my 05 Sierra 4.3L for months and turned out to be the gas cap.