INIT2WIN

iTrader: (8)

I've been fighting a multi cylinder missfire and insuficiant switching on both O2s. I had a noticeable slight missfire at idle for a while. I swaped out my plugs to TR55s and brand new MSD 8.5mm wires. The miss was still there and it would throw a SES every other day or so. I jus put in 2 new AC Delco O2s about 5 days ago. I unpluged my battery for an hour or so to reset my ECM after the O2 swap. The car runs great now no noticeable missfire at idle anymore. Driving to work this morning and the SES light pops on for multi cylinder missfire and infuiciant switching on both brand new O2s! I'm ready to drive this car into a ditch! Can anyone shed sum much needed light on what i may be missing, or what else could be going wrong?

Thanks!

Otto j

Get a scanner on it and see what the long and short term fuel trims are doing.
this will give more info to go on.
I am curious if they are staying positive or negative correction

thedrill

iTrader: (1)

Check engine to chassis ground, also battery terminals for good connections.
We had a similar fault that turned out to be a ground issue.