LOW OR ROUGH IDLE FOLLOW DECEL REVISED HOT IDLE CALIBRATIONS

SUBJECT: LOW OR ROUGH IDLES FOLLOWING DECELERATION (REVISED HOT IDLE CALIBRATIONS)

VEHICLES AFFECTED: 1992 "R" CAR WITH 1.6/1.8L ENG. (VIN 6,8) M/T GEO STORM ASUNA SUNFIRE

CONDITION:

---------- A limited number of 1992 Geo Storm and Asuna Sunfire ("R"- cars) equipped with manual transaxles may exhibit low or rough idles immediately following a deceleration.

CAUSE:

------ Original ECM (Emission Control Module) calibration did not fully address idle instability at ambient temperatures over 27 degrees C (80 degrees F). In severe cases, the low idle may result in a stall. If normal service procedures do not correct the condition, the following calibrations have an improved idle air control feature which will stabilize the rough idles.

CORRECTION:

----------- Reprogram ECM "EE Prom", using TECHLINE equipment, with revised calibration part numbers listed below:

EMISSION CALIBRATION ENGINE SYSTEM TRANS NUMBER ------ -------- ----- ----------- 1.6L SOHC (VIN 6) FED. M/T 16165809

1.8L DOHC (VIN 8) FED. M/T 16166629

For vehicles repaired under warranty use:

Labour Operation: J6355 Labour Time: 0.3 Hr. (EE Prom Reprogramming)

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.