P0302 - Misfire Cylinder 2: need help troubleshooting

[ecordell]

Try your O2 sensor underneath the passenger seat.

 

[07 black beauty]

Do or have a compression check done on cylinders. With a 5.3 that has AFM\DOD, most likely it will be a lifter issue.
and if it is related to AFM and you have it repaired, please get the AFM crap deleted or at least disabled.

 

[DesertRat]

Do or have a compression check done on cylinders. With a 5.3 that has AFM\DOD, most likely it will be a lifter issue.
and if it is related to AFM and you have it repaired, please get the AFM crap deleted or at least disabled.

checked compression on the front four cylinders, all were around 170/180. I'm going to check wires next. I disconnected the #2 injector wire and no noticeable change. Just have to take the time to chase the wires and check continuity

 

[DesertRat]

maybe a bad injector, maybe it has a intake leak?, I would test for a intake leak and maybe swap injectors

This looks like it might be the winning answer. Last weekend I replaced the intake and valve cover gaskets, and I noticed an immediate difference at idle and overall performance. Gasket at cylinder #2 was noticeably not sealed correctly. Even after idling for prolonged periods of time this week, the CEL did not come back on. It's only been a week though, so it's not been thoroughly tested.

After rereading my first post, I should clarify that in most instances the CEL came on after idling for several minutes.