1987 T1 Shelby Charger. Car has been running fine for two weeks. Went to DMV, and right in the middle of the emissions test, the Idle starts jumping from 1000 to 3000 and a few points in between. Symptoms:
1) When car hit about 3000, Power Loss triggers and Idle drops to 500-1000, then back up. It cycles like this, sometimes gets stuck at 3000 for 3 or 4 seconds, then Power Loss and drop.
2) My boost gauge shows 20 on vacuum, but doesn't seem to get past 0 now when I hit throttle. Not sure how normal behavior is.
3) When I turn off car, Tach is showing needle stuck at 2000 sometimes.
4) Removed two wires on AIS, the Idle Control motor on the TB. No change in behavior.
5) Checked all the vacuum lines I can think of, all look good.
6) No Codes. Just 55 on the dash when I do the key on-off thing.
So I figure some sensor went bad? The car was idling for a while in line and in the test area. Maybe heat destroyed a sensor?
Any ideas?? I need to this through inspection, I obviously have a nice big red REJECTED sticker and I had to get towed home...
Thanks! I am home now to try anything out!
Derek