Skyhawk L4-121 2.0L VIN K TBI (1987)
![background image](/buick/skyhawk/l4-121_2.0l_vin_k_tbi/Page-1257001.png)
PROM - Programmable Read Only Memory: All Technical Service Bulletins
Engine - Surge/Unstable Idle
Bulletin 87-6E-3
Date 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