ENGINE CHUGGLE AT LOW SPEEDS RAISE TCC SPEED (PROM)

SUBJECT: ENGINE CHUGGLE AT LOW SPEEDS (RAISE TORQUE CONVERTER CLUTCH (TCC) LOCK UP SPEED)

VEHICLES AFFECTED: 1989-91 J CAR W/2.0L, 1989 N CAR W/2.5L

* THIS BULLETIN HAS BEEN REVISED TO INCLUDE THE 1990 AND 1991 J CAR WITH 2.0L ENGINE.

CONDITION:

--------- Some owners of 1989-91 J cars with 2.0L Vin 'K' and 1989 N cars with 2.5L Vin 'U' engines may comment of an engine shudder or chuggle condition when driving at slow speeds in high gear.

CAUSE:

----- Converter clutch lock up at slow speeds during some driving conditions.

1989 - 1991 J-Car with 2.0L Engine (Vin Code 'K') --------------------------------------------------

From 37 to 63 KPH (23 to 39 MPH)

Usage PROM PKG. P/N Broadcast Code Scanner I.D. ----- ------------- -------------- ------------ All 16157159 AWSP 7171

1989 N-Car with 2.5L engine (Vin Code 'U') ------------------------------------------

From 47 to 69 KPH.(29 to 43 MPH)

Usage PROM PKG. P/N Broadcast Code Scanner I.D. ----- ------------- -------------- ------------ All 16157765 AWDT 7781

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.