Subject: HARD STARTING DURING A HOT RESTART, INCREASE IN IDLE SPEEDS, AND IDLE FLUCTUATION (REPLACE MEM-CAL)
Model and Year: 1990-91 CHEVROLET CORVETTE WITH 5.7L ENGINE (VIN J - RPO LT5) AND MANUAL 6-SPEED TRANSMISSION (ML9)
Source: Chevrolet Service Bulletin
Bulletin Number: 47-65-03 - (01/24/1994)
SOME OWNERS OF 1990 CORVETTES MAY COMMENT ON IDLE FLUCTUATION, INCREASE IN IDLE SPEED AFTER A HOT RESTART, AND AN INCREASE IN ENGINE SPEED DURING A VEHICLE COAST TO STOP WITH CLUTCH DEPRESSED.
SOME OWNERS OF 1991 CORVETTES MAY COMMENT ON A HARD STARTING CONDITION DURING A HOT RESTART.
THE CALIBRATIONS HAVE BEEN REFINED TO ADDRESS THESE CONCERNS. REPLACE THE MEM-CAL WITH THE DESIRED UNIT FROM THE CHARTS BELOW.
MODEL BROADCAST SCANNER PART BODY YEAR CODE I.D. NUMBER STYLE AXLE
----- --------- ------- ------ ----- ----
1990 AYBK 3921 16163905 COUPE 3.45
1991 BFXB 3431 16193416 COUPE 3.45
PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.
LABOR OPERATION: T0500 LABOR TIME: 0.5 HOUR
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.
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Article ID: 484
Created: July 24, 2014
Last Updated: July 24, 2014
Online URL: https://www.corvetteactioncenter.com/tech/knowledgebase/article/1990-1991-corvette-service-bulletin-hard-start-on-hot-restart-increased-idle-speed-484.html