cameronc

Well here's results from today's testing. Fuel pressure koeo 64psi, idling 44psi. Compression bank 2-Full throttle, 4 revolutions. #2 220psi, #4 225psi, #6 230psi, #8 230psi Double checked plug gap at .040 Ecm is in control of fuel trims. Both banks run between -5.0 & +5.0. I can pump brakes and drive both banks lean and add fuel to intake and drive them rich. B1s1 and b2s1 ho2 both steady switching. Maf graph is steady consistent with throttle pedal.

Already replaced plugs, wires, and injectors. Scanner doesn't pick up any misfires out of range. I haven't done a leak down compression test on bank 2 yet. Thats my next step but I just don't understand why the code sets because the freeze frame data shows bank 1 and 2 both very close and not crazy lean. Also ran seafoam upper intake cleaner through intake but I'm not going to say that definitely cleaned carbon.

I've diagnosed issue with scanner for months now trying to fix problem without success. I've replaced parts I didn't think were bad but I don't know what else to do to fix. Replaced o2 sensors with genuine gm. Tune up. Replaced fuel injectors. Checked for vacuum leaks. Tested fuel pressure. The freeze frame data when the code sets don't seem out of range to me. Both banks seem normal. The fuel trims are good and the maf is in range. No misfire codes at all although it has had a rough idle since I purchased 3 years ago with 100k on it. Now has 140k. Runs great just rough idle. Misfire data on scanner doesn't show anything out of range on either bank. I have more info if someone interested in helping. Thanks