Gmc 4.3

[jpownell]

Hey guys. Got an 04 1500 here. Check engine blinks. Very rough idle around 650 rpms. Truck wouldn't start for two weeks so I've changed plugs worse cap rotor coil and crank sensor. Tried changing fuel filter but it's rusted on. Swapped relays for the fuel pump and now it starts but it's very rough idle and exhaust smells like pure eggs. There's a random pop through exhaust and the whole truck shakes. Any ideas? Any help thanks. Plus I'm a ford and Chrysler guy with my 04 ls6 and an old 4x4 dakota. Trying to help a buddy out here with his gmc. Thank you!
Justin

 

[slowmkviii]

Sound like it could be a clogged cat.

 

[chicken]

could be a lot of things, the fuel filter could be clogged, the pump could be on its way out, the 4.3 is a "cpi" (central port injection) and it has small hoses running from the center of the upper intake to the "injector" down near the head, those can crack and puke fuel all over inside the lower causing them to run like ass. bad thing is you have to pull the upper intake too see

 

[slowmkviii]

No in 03+ all 4.3s were mpfi