Hopefully you guys can help me out...I installed new NGK G-power platinum plugs, Taylor Spiro 8mm wires, and cat delete pipes over the weekend. The car was then running really poorly: stumbled, missed, lost lots of power. Plugs said not to gap them, they were all around .057-.058, where stock is .050.

SES light started flashing on the drive afterward. Had PCM scanned, and came up with P0174, bank 2 lean...checked wires again, and #2 was not snapped on @ opti, so I fixed it, and its a little better, but still stumbles really bad under load.

SES light is still flashing, and still running very poor right now. 1 O2 sensor is brand new, other is about 6000 miles, couple of months old. I did leave old sensors plugged into the pos. 2 because I didn't want to get the harness all messed up...

I thought the gaps might cause a problem, so I installed TR55 Iridiums gapped correctly at .050, and it runs a little better, but still pretty crappy. Also removed rear O2's...

I don't know if it would have anything to do with it, but I did change the oil too when I did the plugs...I read in a post about miss problems, then an oil change fixed it. Another one said that not enough oil in the lifters (failing oil pump) caused a miss too.

I also read about the CPS messing up spark too, and I did unplug it for easier access to the wires from underneath, but its reconnected and nothing broke visibly, but could something else have happened

Thanks in advance for any info.

-Jeremy

 

Anybody???

 

Did you disconnect the front O2's while you were doing any work?

As far as it running crappy, did you double check the plug wires to the correct plug?