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

MODEL AND YEAR: 1986 MONTE CARLO & EL CAMINO WITH 5.0L ENGINES (V.I.N. CODE H) AND THM-200-4R TRANSMISSIONS

TO: ALL CHEVROLET DEALERS

Some 1986 Monte Carlo and El Camino Model Vehicles with the 5.OL engine and 4 speed automatic transmission may experience the following customer comments of:

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

If normal service procedures in the Shop Manual do not correct the customer comments, a new service PROM with revised calibration is now available.

MODEL - PROM APPLICATION ------------------------

Year Model Engine Trans. Emissions Service ---- ----- ------ ----- ---------- PROM P/N --------

1986 Monte Carlo 5.OL 4 Spd Auto California 1228478 El Camino

1986 Monte Carlo 5.OL 4 Spd Auto Federal 1228479 El Camino

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.