For 1990-2009 cars

# INFO ON POPPING OR THUMP NOISE

#### SUBJECT: INFORMATION ON POPPING OR THUMP NOISE FROM LEFT REAR OF VEHICLE

#### MODELS: 1996-97 BUICK LESABRE 1996-97 OLDSMOBILE EIGHTY EIGHT 1996-97 PONTIAC BONNEVILLE WITH 3.8L ENGINE (VIN K - RPO L36)

ON SOME OF THE ABOVE LISTED VEHICLES, A SUBTLE POPPING OR THUMP NOISE MAY BE HEARD COMING FROM THE LEFT REAR OF THE VEHICLE DURING THE FIRST 3 TO 5 MINUTES AFTER A COLD START.

THIS NOISE OCCURS DURING A COLD START OBD II FUEL SYSTEM VACUUM LEAK CHECK AND SHOULD BE CONSIDERED A NORMAL CONDITION.

NO CORRECTIVE ACTION IS NECESSARY. DO NOT REPLACE ANY FUEL SYSTEM COMPONENTS, INCLUDING THE FUEL TANK. THE TANK NOISE WILL NOT CAUSE ANY LOSS OF FUNCTIONAL PERFORMANCE OF THE FUEL SYSTEM.

FIGURES: 00 ATTACHMENTS: 00

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 1997 GENERAL MOTORS CORPORATION. ALL RIGHTS RESERVED.