Papikev252
Newbie
Been chasing this P0300 for a while now. 98 K3500 7.4L
Hooked up a scanner to view misfire data and it’s all over the place with 2 & 3 and 6 & 7 being the worst. I’ve replaced every ignition component, spark plugs gapped at .45, new Bosch fuel injectors. New crank position sensor and did a crank relearn. I did the upper intake manifold when I did the fuel injectors and also tested with a noid light to make sure they were all getting voltage. CMP is at 0, I’ve done a compression test and all were within 150-160 psi. Fuel Pressure is 60 with KOEO, and 55 when running. I’ve also replace the O2s with Bosch. It’s only at idle when the misfires occur, when I’m driving there are none whatsoever. I’ve smoke tested everything for leaks and don’t see anything leaking out. I’m at a loss, I have a scanner so maybe some insight of what to look for? I see sometimes the ECM may be an issue maybe was going to go that route.
Hooked up a scanner to view misfire data and it’s all over the place with 2 & 3 and 6 & 7 being the worst. I’ve replaced every ignition component, spark plugs gapped at .45, new Bosch fuel injectors. New crank position sensor and did a crank relearn. I did the upper intake manifold when I did the fuel injectors and also tested with a noid light to make sure they were all getting voltage. CMP is at 0, I’ve done a compression test and all were within 150-160 psi. Fuel Pressure is 60 with KOEO, and 55 when running. I’ve also replace the O2s with Bosch. It’s only at idle when the misfires occur, when I’m driving there are none whatsoever. I’ve smoke tested everything for leaks and don’t see anything leaking out. I’m at a loss, I have a scanner so maybe some insight of what to look for? I see sometimes the ECM may be an issue maybe was going to go that route.
