SURGE AFTER TCC ENGAGEMENT NEW PROM P/N'S LISTED. GMC Truck Caballero 1986

For 1990-2009 cars

# SURGE AFTER TCC ENGAGEMENT NEW PROM P/N'S LISTED

#### MODELS: 1986 CABALLEROS WITH 5.OL ENGINES (VIN CODE H) AND THM 200-4R AUTOMATIC TRANSMISSIONS

Some 1986 Caballeros with the 5.OL engine and 200-4R 4-speed automatic transmission (MW9) may experience the following conditions:

1. Surge after TCC lock-up 2. Detonation on light acceleration. 3. False Code 53 - EGR Control Error.

If the service procedures in Section 6E-Drive- ability and Emissions of the appropriate service manual do not correct these conditions, a new service PROM with revised calibration is now available.

#### PARTS INFORMATION

Service Year Model Engine Transmission Emissions Prom P/N ---------- ------ ---------------------- -------- 1986 Caballero 5.OL 4-Speed California 1228478 Automatic 1986 Caballero 5.OL 4-Speed Federal 1228479 Automatic

PROM replacement procedures are in Section 6E- Driveability and Emissions of the service manual.

Use applicable labor time and operation numbers.

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.