For 1990-2009 cars

# ENGINE WHINE BETWEEN 2000-3000 RPM REPL. CRANKSHAFT SPROCKET

********************************************************************* SUBJECT: ENGINE WHINE NOISE BETWEEN 2000 - 3000 RPM WITH NO LOAD ON ENGINE (REPLACE CRANKSHAFT SPROCKET)

#### MODELS: 1992-93 PONTIAC GRAND AM 1992-93 OLDSMOBILE ACHIEVA 1992-93 BUICK SKYLARK (EQUIPPED WITH 2.3L (L40) ENGINE)

#### CONDITION:

SOME CUSTOMERS MAY COMMENT ABOUT A WHINE NOISE COMING FROM THE ENGINE BETWEEN 2000 AND 3000 RPM WITH NO LOAD ON THE ENGINE.

#### CAUSE:

THE WAY THE CRANKSHAFT SPROCKET TEETH CONTACT THE TIMING CHAIN CAUSES THE WHINE NOISE.

#### CORRECTION:

REPLACE THE CRANKSHAFT SPROCKET WITH A REVISED CRANKSHAFT SPROCKET P/N 24574600.

#### SERVICE INFORMATION:

USE THE PROCEDURE IN SECTION 6A7 IN THE SERVICE MANUAL. THERE HAS BEEN NO CHANGE IN THE REMOVAL AND INSTALLATION PROCEDURE.

THE REVISED PART CAN BE IDENTIFIED BY THE ALIGNMENT MARK. THE NEW PART WILL HAVE A STRAIGHT ALIGNMENT MARK AND THE OLD PART HAS A DOT FOR AN ALIGNMENT MARK.

VEHICLES BUILT AFTER JUNE 1993 WILL HAVE THE UPDATED CRANKSHAFT SPROCKET.

#### PARTS INFORMATION:

DESCRIPTION PART NUMBER ----------- ----------- CRANKSHAFT SPROCKET 24574600

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

#### WARRANTY INFORMATION:

LABOR OPERATION: J0830 - SPROCKET, CRANKSHAFT TIMING - REPLACE USE PUBLISHED LABOR OPERATION TIME. TROUBLE CODE 92

FIGURES: 0

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.

COPYRIGHT 1993, GENERAL MOTORS CORPORATION. ALL RIGHTS RESERVED.