ENGINE SURGE ON DECEL/ERRATIC SPEED W/CRUISE ON-NEW GOVERNOR

Subject: ENGINE SURGE ON DECEL, VEHICLE SPEED ERRATIC W/CRUISE ON-RANGE OF 1-5 MPH, NO UPSHIFT (GOVERNOR ASSEMBLY)

Models Affected: 1991 SUNBIRD, GRAND AM AND GRAND PRIX MODELS

BULLETIN COVERS:

A new governor assembly (4) which contains a high glass content driven gear. Some owners of 1991 vehicles equipped with HYDRA-MATIC 3T40 transaxles may comment on one or more of the following conditions:

- Engine Surge on Deceleration, Surge with Cruise Control Engaged or Vehicle Speed Erratic (range of 1 to 5 MPH). These may be caused by worn teeth (thin) on the governor driven gear.

- No Upshift and Stuck in First Gear. These conditions are caused by an applecored governor driven gear.

SERVICE PROCEDURE:

If any of the above mentioned conditions exist, replace the entire governor assembly with a new high glass content governor, transaxle fluid strainer (33) and seal (32) assembly. This new high glass content governor may be used on transaxles built prior to December 14, 1990 (Julian Date 348) . This new high glass content governor driven gear may cause a polished look on the governor drive gear located on the Final Drive (679) but will not affect transaxle durability.

SERVICE PARTS INFORMATION:

Whenever ordering the new high glass content governor, refer to the following part numbers:

*Description Model Part Number ------------------ ------ ------------ Governor Assembly AYC 8682985 " " KDC 8682987 " " KXC 8682989 " " LYC 8682991 " " PNC 8682993 " " TRC 8682995

*Each governor package also contains a filter, multi-lip seal and bottom pan gasket.

SERVICE MANUAL REFERENCE:

Refer to the On-Vehicle Service Section of your Service Manual whenever replacement of a governor assembly is necessary.

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.