Coils smoothed things out a little but today i went to re-route the wires and im pretty sure i found the culprit. The plug for the #4 cylinder was loose, i could easily turn it with my fingers. All i can guess is that when i did the PEM install i didn't tighten them enough and that one vibrated loose. If that'* what this has been due too it will be pretty frustrating. :(

Damn well at least it looks promising now! Yeah those wires gotta make a click on the plug to be sure.

It may be frustrating to find out that it was something as "simple" as a loose spark plug, but if that turns out to be the cause, at least it will be an inexpensive fix.

The torque settings for the plugs are: 20 ft lbs for new plugs, and 11 ft lbs for reinstallation of old plugs.

Loose as in not pushed on all the way?

If you had NGK plugs..one of my first suggestions would have been to pull wires and check the ends to make sure they were screwed on all the way. NGK'* have screwed on ends..Autolites don't

I think that we have some confusion with this statement.
Was it the spark plug, or the plug wire that was loose?

I can't quite remember what all was stated, but I remember seeing a TSB not too long ago for the 2000+ Bonne'* and a chugging/surging while accelerating.

The only TSB I could find regarding that was for dirty injectors. Perhaps that one?

the Autolite 605 on the #4 cylinder was loose in the engine. the wire was snapped on correctly but the plug was finger loose.

Don't know how effective it is but i ran a bottle of GM injector cleaner through my system ~5,000 miles ago.

Make: PONTIAC
Model: BONNEVILLE
Year: 2000

Service Bulletin Number: 050604058
NHTSA Item Number: 10017568
Summary Description:
INTERMITTENT CHUGGLE OR FISHBITE ON LIGHT ACCELERATION OR A HIGHWAY SPEEDS WITH NO DIAGNOSTIC TROUBLE CODES (DTCS). *TT