GM Service Manual Online
For 1990-2009 cars

HARSH 1-2 UPSHIFT DURING ACCEL REPLACE PCM AND CALIBRATION

SUBJECT: Harsh 1-2 Upshift During Light Throttle Acceleration (Replace PCM and Download New Calibration)

MODELS AFFECTED: 1991 SL2 Sedans and SC Coupes equipped with MP7 automatic transaxle

CONDITION:

A harsh 1-2 upshift may be experienced during light throttle accelerations. This condition is most noticeable when the transaxle is at, or above normal operating temperature.

CAUSE:

Under certain driving conditions, the PCM/TC adaptive process may improperly adjust clutch fill times, resulting in a harsh 1-2 upshift, when accelerating from a stop, with a throttle opening between 12 and 20 percent.

CORRECTIVE ACTION: Refer to the following flow -chart to determine what corrective action should be taken.

PARTS REQUIREMENTS: 21022155 Powertrain Control Module - Engine Gas, 4 - Cyl, 1.9L, MFI, DOHC (LLO) - Auto. Trans. MP7

CLAIM INFORMATION: To receive credit for this repair, submit a claim through the Saturn Dealer System as follows:

Labor Case Operation Type Description Code Time ---- ----------- --------- ---- VW Controller, PCM-Replace T9571 0.3 hrs

When returning the PCM, include the following information: "PCM replaced for transaxle service calibration."


Object Number: 78233  Size: FS

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.