Question I have a low idle miss it will set the service engine soon
lite. I've changed the plugs,wires,#2 injector,and the coil.
It still has a low idle miss. The compression is good. The
missfire causes a real high hydrocarbon read and will not
pass the california biannual smog check because of it.
AnswerHi
3 ideas from everything you say has been done, and the miss still exists.
1) a partially stuck open EGR valve OR a cracked upper plenum (COMMON PROBLEM ON THESE ENGINES) creating internal EGR leaks, or allowing coolant to enter the air supply.
2)An engine mechanical problem. e.g. low oil pressure not pumping up a lifter at low RPM. A valve just barely sticking. A slightly worn cam lobe. ANY low oil pressure related concern. Check the ACTUAL oil pressure with a gauge hooked to the engine, dont rely on the gauge on the dash.
3) A Leaky fuel presssure regulator. Take the vaccuum line off the regulator, if there is ANY sign of gasoline, either smell or actual liquid it IS bad. There should be NO fuel in that vacuum hose.
If it is ONLY the #2 cylinder, I would again to double check yourself, swap all the new parts(Injector and plug)to another cylinder, like the #3 cylinder.
See if the misfire follows the parts.
If so one of your new parts is faulty.
If not I really would suspect an engine mechanical problem.
Hope this helps
JUST advice from experience.
Good Luck
Pawl
