Jumping in sideways for a minute. On those grounds, you should also have some others at:
- - The other ICM mounting stud.. not where the battery to block ground is.. the OTHER stud. That is where the PCM gets its ref. ground on mine.
-Also, one on each front fender, under the hood
-And, one behind each front kick panel. May be up, sort of high
I saw some discussion about vacuum earlier. If you get desperate, you can eliminate possibility of vacuum causing it, if you block ALL your vacuum inlets at the vacuum tree. You probably could not test drive it this way, but could clear the code and see if it comes back just idling and revving, etc, in Park. Of course, if it is still there, you can concentrate on the other stuff.
One last note; had one member who was running lean and finally found a bad brake booster as the culprit. Yeezch!
I'm back out of here.
1993 Red SSE - Bone-Stock except for High Perf. Power Antenna-Original Owner. Less than 130K - Love of my Wife
'05 Magnum R/T Hemi - Bunches of classic VW Beetles... and one "not quite stock."