HESITATION, SAG OR CHUGGLE ON ACCELERATION (INSTALL EPROM). Chevrolet Corsica 1991

REVISION: 02/14/94

THIS BULLETIN IS BEING REVISED TO CHANGE THE RPO CODE FOR THE 1990-91 CHEVROLET BERETTA. ----------------------------------------------------------------------

1990-91 CHEVROLET BERETTA (WITH 2.3L ENGINE - VIN A - RPO LG0)

SUBJECT: HESITATION, SAG OR CHUGGLE ON ACCELERATION DURING WARM-UP (DIAGNOSE/INSTALL NEW EPROM)

MODELS: 1990-92 PONTIAC GRAND AM 1990-92 OLDSMOBILE ACHIEVA 1990-92 BUICK SKYLARK (WITH 2.3L ENGINES - VINS A,D,3 - RPOS LG0, LD2, L40)

1990-91 CHEVROLET BERETTA (WITH 2.3L ENGINE - VIN A - RPO LG0)

1990-91 PONTIAC GRAND PRIX 1990-91 OLDSMOBILE CUTLASS SUPREME (WITH 2.3L ENGINE - VIN D - RPO LD2)

SOME OWNERS MAY EXPERIENCE A DRIVEABILITY CONCERN SUCH AS HESITATION OR SAG DURING THE FIRST TWO MINUTES OF COLD OPERATION WHILE VEHICLE IS UNDER MODERATE TO HEAVY THROTTLE DRIVEAWAY, OR THEY MAY EXPERIENCE A TORQUE CONVERTER CLUTCH (TCC) CHUGGLE.

IF THE ABOVE CONDITIONS EXIST AFTER FOLLOWING PROPER SERVICE MANUAL DIAGNOSIS, IT MAY BE NECESSARY TO INSTALL A NEW MEM-CAL/EPROM TO CORRECT THE DRIVEABILITY CONCERN.

"N" CAR NEW MEM/CAL/ BROAD- EPROM MEM-CAL/ CAST MODEL VIN EMISS. TRANS EXHAUST SCAN ID EPROM CODE COMMENTS ----- --- ------ ----- ------- ------- ------- ----- -------- 1990 A FED MAN N/A 1773 16191778 BFLD 1 1990 A CALIF MAN N/A 1783 16191779 BFLF 1 1990 D FED AUTO N/A 1793 16191780 BFLH 1, 2 1990 D CALIF AUTO N/A 1803 16191782 BFLJ 1, 2 1991 A FED MAN N/A 1833 16191788 BFLM 1 1991 A CALIF MAN N/A 1843 16191789 BFLN 1 1991 D FED AUTO SINGLE 1853 16191790 BFLP 1 1991 D CALIF AUTO SINGLE 1863 16191792 BFLR 1 1991 D FED AUTO DUAL 1873 16191795 BFLS 1 1991 D CALIF AUTO DUAL 1883 16191797 BFLT 1 1992 3 FED AUTO N/A 1733 16191769 BFKZ 1 1992 3 CALIF AUTO N/A 1743 16191772 BFLA 1

"L" CAR

1990 A FED MAN N/A 1753 16191775 BFLB 1 1990 A CALIF MAN N/A 1763 16191777 BFLC 1 1991 A FED MAN N/A 1813 16191785 BFLK 1 1991 A CALIF MAN N/A 1823 16191787 BFLL 1

"W" CAR

1990 D FED AUTO N/A 2393 16192678 BFNZ 1, 2 1990 D CALIF AUTO N/A 2403 16192682 BFPA 1, 2 1991 D FED AUTO N/A 2583 16192725 BFRH 1 1991 D CALIF AUTO N/A 2593 16192732 BFRJ 1

COMMENTS:

1. THE MEM-CAL/EPROM IS TO REPAIR HESITATION OR SAG WHEN THE AMBIENT TEMPERATURE IS AROUND 0 - 15 DEGREES CELSIUS DURING THE FIRST TWO MINUTES OF ENGINE OPERATION. 2. THE MEM-CAL/EPROM IS TO REPAIR TORQUE CONVERTER CLUTCH (TCC) CHUGGLE.

IF THE ABOVE CONDITION CANNOT BE REPAIRED THROUGH THE ABOVE DIAGNOSIS, REFER TO CORPORATE BULLETIN 076001 (OLDSMOBILE 90-T-157 AND PONTIAC 90-6-45) FOR 2.3L ENGINE INTAKE VALVE DEPOSITS.

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.