Bought a 2000 Impala LS for my daughter...beautiful car...but it has an intermittent misfire that I can't figure out that is driving me crazy....help me please??? It is not triggering the Check Engine light.... on my Actron and my AutoXray scanner it is not showing any misfires in the cylinders. I have replaced the plugs/wires, intake gaskets, coil packs and ignition module....still I have a misfire..... most of the time it idles beautifully and runs beautifully. Then out of no where while sitting idling it'll cough and pick back up (and occasionally die). OR while driving it'll cough, RPM gauge drops, then it picks pack up and moves on just fine....... "MOST" of the time it runs/drives just fine...there is no routine to it'* misfire....sometimes while accelerating from a stop, but not always....this is driving me crazy................ Please help... I wanna give this to my daughter this week....................... thanks.

https://www.gmforum.com/chevrolet-17...no-cel-307996/

please keep your problems to one thread it will confuse people

Okay, I had a similar problem with a 3.1L V6 in an '01Malibu. I replaced the OEM plugs and wires with aftermarket and I kept getting misfires and codes so I went to the Chevy dealership and bought a set of OEM plugs and wires and all of my misfire troubles went away forever.
Hope this helps.