Any GM service techs?

[b.lee]

A few months after the plugged cats, I also put the updated intake gasket in because of super rough idle (only when the engine is cold)

 

[SuperStang90]

A misfire code CAN be present with lean or rich conditions FYI.

 

[dave89iroc]

I have seen several of those with a bad upstream o2 on 1 side causing the PCM to think it was lean and adding so much fuel that it was misfiring on just the 1 bank

you can try unpluging the o2 on that side, see if it still misses, it not, tyou can swap the upstreams and see if the other bank starts misfiring

 

[Beigg]

bad injector coil.

 

[smooth]

Someone also told me cam positioning sensor?

 

[adam351]

make sure the crankshaft position sensor is learned !!!

 

[WhiteHawk]

Someone also told me cam positioning sensor?

Cam sensor just gives you long crank times - PCM uses crank sensor to find TDC than has to guess where the cam TDC is so it takes longer.

-Geoff