For 1990-2009 cars

# POOR COLD START/HESITATION/SAG AIR CONDITIONER PERFORMANCE

#### SUBJECT: POOR COLD START, HESITATION OR SAG AND/OR POOR AIR CONDITIONER PERFORMANCE (REPLACE MEMCAL)

#### MODELS: 1990-93 BUICK CENTURY 1990-93 OLDSMOBILE CUTLASS CIERA WITH 3300 V6 ENGINE (VIN N - RPO LG7)

#### CONDITION:

TWO CONDITIONS ADDRESSED WITH THE SAME MEMCAL:

1. SOME VEHICLES MAY EXHIBIT A CONDITION DESCRIBED AS A "COLD START-STALL," "HESITATION," OR "SAG" WHEN THE ENGINE COOLANT IS BETWEEN 36 TO 111 DEGREES FAHRENHEIT (2 TO 44 DEGREES CELSIUS).

2. SOME OWNERS MAY EXPERIENCE INADEQUATE AIR CONDITIONER PERFORMANCE WHEN DRIVING AT A STEADY SPEED AND THROTTLE POSITION, BETWEEN 24 TO 64 MPH, WHEN THE CRUISE CONTROL IS NOT BEING USED.

#### CAUSE:

TWO CAUSES, DEPENDING ON THE CONDITION BEING ADDRESSED:

1. VARIABILITY IN VOLATILITY OF FUELS MAY CAUSE THE AIR/FUEL RATIO TO BE TOO LEAN UPON COLD START UPS (SEE STATEMENT 1 UNDER CONDITION).

2. THE MEMCAL SOFTWARE OPERATING SYSTEM MAY CAUSE THE AIR CONDITIONING COMPRESSOR TO SWITCH OFF DURING EXTENDED STEADY SPEED AND THROTTLE POSITION WHILE DRIVING WITHOUT USING CRUISE CONTROL (SEE STATEMENT 2 UNDER CONDITION).

#### CORRECTION:

ONE MEMCAL CORRECTS BOTH CONDITIONS:

1. IF CONDITIONS OUTLINED IN SECTION 6E3-B OF APPROPRIATE SERVICE MANUALS ARE NOT CAUSING THE HESITATION OR SAG, A SERVICE MEMCAL IS AVAILABLE TO SLIGHTLY ENRICH THE COLD START AIR/FUEL RATIO, COMPENSATING FOR THE VARIANCE IN VOLATILITY OF DIFFERENT FUELS. NO OTHER DRIVEABILITY ISSUES ARE ADDRESSED WITH THIS MEMCAL (SEE STATEMENT 1 UNDER CONDITION).

2. VERIFY, BY ROAD TESTING, THE INADEQUATE AIR CONDITIONER PERFORMANCE CONCERN OCCURS ONLY BETWEEN 24 TO 64 MPH:

- STEADY SPEED AND THROTTLE POSITION - CRUISE OFF

IF THE ROAD TEST CONFIRMS THE COMMENT, REPLACE THE MEMCAL. THIS MEMCAL WILL NOT CORRECT FOR INADEQUATE AIR CONDITIONER PERFORMANCE OCCURRING ABOVE 64 MPH AND/OR BELOW 24 MPH, INCLUDING IDLE. ALSO, IF INADEQUATE AIR CONDITIONING OCCURS WITH THE CRUISE CONTROL **ON** (UNDER ANY CONDITION), NO CORRECTION WILL BE MADE BY USING THIS MEMCAL (SEE STATEMENT 2 UNDER CONDITION).

#### SERVICE INFORMATION:

USE THE PROCEDURE IN SECTION 6E3 IN THE SERVICE MANUAL FOR MEMCAL REPLACEMENT.

#### PARTS INFORMATION:

BC MEMCAL PART NUMBER CODE ID EMISSIONS TRANSMISSION DIVISION ----------- ---- ------ --------- ------------ -------- 16211978 BNAK 1984 NW (FED/CALIF) 3T40 (3 SPD) BUICK, OLDS 16208288 BLYB 8314 NW (FED/CALIF) 4T60 (4 SPD) BUICK, OLDS

PARTS ARE EXPECTED TO BE AVAILABLE FROM GMSPO ON OCTOBER 3, 1994.

#### WARRANTY INFORMATION:

LABOR OPERATION: J6364 LABOR TIME: 0.6 HOUR

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 1994. GENERAL MOTORS CORPORATION. ALL RIGHTS RESERVED.