Engine - Surge/Unstable Idle
Bulletin 87-6E-3Date Dec., '86
Ref. No. 87-036-6E
SUBJECT: ENGINE CALIBRATION PROMS TO IMPROVE IDLE SPEED STABILITY AND LESSEN SURGE ON DESCENDING LONG GRADES
MODELS AFFECTED: SOME 1987 SKYHAWKS EQUIPPED WITH 2.0L OHV-TBI ENGINES (VIN CODE 1)
There may be customer comments on some early production Skyhawks, concerning the following conditions:
1. Surge on long descending grades with a slightly cracked throttle, and more pronounced at higher altitudes with either a manual or automatic transmission.
2. Unstable idle speed on higher mileage manual transmission vehicles only, where the idle RPM will oscillate up to 300 RPM over a continuous period with steady operating conditions.
The following is a listing of Service PROMS and their appications:
"J" Body Automatic Transmission Service PROM #16071643
"J" Body Manual 4-Speed Transmission Service PROM #16071647