ENGINE CHUGGLE AT LOW SPEEDS NEW PROM PACKAGE

SUBJECT: ENGINE CHUGGLE AT LOW SPEEDS (NEW PROM PACKAGE TO RAISE TCC LOCKUP SPEED)

MODELS AFFECTED: 1990 SKYLARKS WITH 2.5L ENGINE (VIN CODE U)

CONDITION:

---------- Some owners of 1990 Skylarks with 2.5L engines may comment about an engine shudder or chuggle condition when driving at slow speeds in high gear.

CAUSE:

------ Converter clutch lockup at slow speeds during some driving conditions.

CORRECTION:

----------- A new PROM package has been released which raises the TCC lockup speed from 29 to 43 mph.

PROM Pkg. P/N Broadcast Code Scanner I. D. ------------- -------------- ------------- 16159793 AXCM 9801

Parts are currently available from GMSPO.

WARRANTY INFORMATION:

Labor Operation Number: T0500 Labor Time: .3 hours

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.