HESITATION, SAG, OR ENGINE STALL DURING COLD DRIVEWAY. Chevrolet Cavalier 1998

REVISION: 02/26/98

THIS BULLETIN IS BEING REVISED TO UPDATE CALIBRATION INFORMATION. PLEASE DISCARD CORPORATE BULLETIN NUMBER 77-65-25 (SECTION 6E-- ENGINE FUEL AND EMISSION). ______________________________________________________________________

SUBJECT: HESITATION, SAG, OR ENGINE STALL DURING COLD DRIVEAWAY MANEUVER (REPROGRAM PCM)

MODELS: 1998 CHEVROLET CAVALIER 1998 PONTIAC SUNFIRE WITH 2.2L ENGINE (VIN 4 - RPO LN2) AND AUTOMATIC TRANSMISSION (MD9, MN4)

CONDITION:

SOME VEHICLES MAY EXHIBIT A HESITATION, ENGINE SAG, OR AN ENGINE STALL DURING LIGHT ACCELERATION (30 PERCENT THROTTLE OR LESS) WHEN THE ENGINE IS COLD. THIS CONDITION MAY BE MORE NOTICEABLE WHEN THE AMBIENT TEMPERATURE IS LESS THAN 10'C (50'F).

VEHICLES INVOLVED:

INVOLVED ARE CERTAIN 1998 J-CAR MODELS EQUIPPED WITH THE 2.2L (RPO LN2) VIN ENGINE CODE 4 ENGINE, THAT FALL WITHIN THE FOLLOWING VIN BREAKPOINTS:

YEAR 1998 DIVISION CHEVROLET MODEL CAVALIER PLANT LANSING PLANT CODE M VIN THROUGH AND INCLUDING WM115495

YEAR 1998 DIVISION CHEVROLET MODEL CAVALIER PLANT LORDSTOWN PLANT CODE 7 VIN THROUGH AND INCLUDING W7156443

YEAR 1998 DIVISION CHEVROLET MODEL CAVALIER PLANT RAMOS ARIZPE PLANT CODE S VIN THROUGH AND INCLUDING WS818867

YEAR 1998 DIVISION CHEVROLET MODEL CAVALIER PLANT GENASYS PLANT CODE B VIN THROUGH AND INCLUDING WB900878

YEAR 1998 DIVISION PONTIAC MODEL SUNFIRE PLANT LORDSTOWN PLANT CODE 7 VIN THROUGH AND INCLUDING W7526103

CAUSE:

CERTAIN FUELS IN COMBINATION WITH VARIATIONS IN MANUFACTURING MAY ALLOW SOME CARS TO RUN LEANER UNDER CERTAIN CONDITIONS.

CORRECTION:

REPROGRAM THE PCM WITH THE REVISED CALIBRATION THAT TAKES INTO ACCOUNT THE ABOVE CONDITIONS. THESE CALIBRATIONS ARE AVAILABLE ON 1997 CD-ROM #19 AND LATER VERSIONS.

CALIBRATION NUMBERS:

USE THE CORRECT CALIBRATION FROM THE LIST BELOW.

ENGINE AND TRANSMISSION LN2 AND 4-SPEED AUTOMATIC TRANSMISSION NEW CALIBRATION NUMBER 09355323 BROADCAST CODE CLKY OLD CALIBRATION NUMBER 09353453 BROADCAST CODE CKHN USAGE LN2 / MN4 / NF2 / NB7 (NATIONWIDE US AND CANADIAN EXPORT)

ENGINE AND TRANSMISSION LN2 AND 4-SPEED AUTOMATIC TRANSMISSION NEW CALIBRATION NUMBER 09355333 BROADCAST CODE CLKZ OLD CALIBRATION NUMBER 09353463 BROADCAST CODE CKHP USAGE LN2 / MN4 / K29 (UNLEADED EXPORT)

ENGINE AND TRANSMISSION LN2 AND 4-SPEED AUTOMATIC TRANSMISSION NEW CALIBRATION NUMBER 09355343 BROADCAST CODE CLLA OLD CALIBRATION NUMBER 09353473 BROADCAST CODE CKHR USAGE LN2 / MN4 / NM2 (LEADED EXPORT)

ENGINE AND TRANSMISSION LN2 AND 3-SPEED AUTOMATIC TRANSMISSION NEW CALIBRATION NUMBER 09355303 BROADCAST CODE CLKW OLD CALIBRATION NUMBER 09353423 BROADCAST CODE CKHK USAGE LN2 / MD9 / NF2 / NB7 (NATIONWIDE US AND CANADIAN EXPORT)

ENGINE AND TRANSMISSION LN2 AND 3-SPEED AUTOMATIC TRANSMISSION NEW CALIBRATION NUMBER 09355313 BROADCAST CODE CLKX OLD CALIBRATION NUMBER 09353433 BROADCAST CODE CKHL USAGE LN2 / MD9 / K29 (UNLEADED EXPORT)

WARRANTY CLAIM INFORMATION: FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

LABOR OPERATION DESCRIPTION LABOR TIME J6355 REPROGRAM PCM (ON CAR) 0.4 HR J6352 REPROGRAM PCM (OFF CAR) 0.4 HR

FIGURES: 0 ATTACHMENTS: 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.