Engine - Low Speed Chuggle

90buick15

Bulletin 90-6E-21


Date Dec. '90


Ref. No. 90-211-6E


Corp. Ref. No. 036518R


SUBJECT: ENGINE CHUGGLE AT SLOW 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