CALIBRATION UPDATE ADDRESSING VARIOUS. Pontiac Firebird 1997

SUBJECT: CALIBRATION UPDATE ADDRESSING VARIOUS DRIVEABILITY CONCERNS (FLASH WITH NEW CALIBRATION)

MODELS: 1997 CHEVROLET CAMARO 1997 PONTIAC FIREBIRD WITH 3800 SERIES II ENGINE (VIN K - RPO L36)

CONDITION:

1. SOME OWNERS MAY COMMENT THAT WHEN CRUISING BETWEEN 20-30 MPH (32-48 KMPH) AND THEN PERFORMING A WIDE OPEN THROTTLE (WOT) MANEUVER FORCING THE TRANSMISSION TO DOWNSHIFT INTO FIRST GEAR, THE ENGINE MAY OVER REV DURING THE 1-2 UPSHIFT. THE OWNER MAY DESCRIBE THE SYMPTOM AS A BUCKING OR ENGINE SURGE SENSATION.

2. ENGINE IDLE SURGE FOR 1-2 MINUTES AFTER STARTING IN 20 - 50 C (68-122 F) OUTSIDE TEMPERATURES.

3. MALFUNCTION INDICATOR LAMP (MIL) ILLUMINATED WITH DIAGNOSTIC TROUBLE CODE (DTC) P0146 STORED IN POWERTRAIN CONTROL MODULE (PCM).

CAUSE:

1. CURRENT PCM CALIBRATION ALLOWS THE ENGINE TO REV UP TO FUEL CUT-OFF DURING THE 1-2 SHIFT CONDITION. WHEN FUEL CUT- OFF IS REACHED (APPROX 5950 RPM) THE PCM SHUTS FUEL OFF TO THE INJECTORS TO PROTECT THE ENGINE FROM BEING DAMAGED DUE TO AN OVER REV CONDITION. THE PCM TURNS THE FUEL BACK ON WHEN THE ENGINE SPEED IS BELOW 5600 RPM.

2. CURRENT PCM CALIBRATION MAY ADJUST THE ENGINE SPARK ADVANCE TOO RAPIDLY DURING THESE TEMPERATURES CAUSING THE IDLE NOT TO BE STABLE.

3. CURRENT PCM DIAGNOSTIC CALIBRATION FOR DTC P0146 MAY BE TOO SENSITIVE.

CORRECTION:

REFLASH THE PCM WITH NEW CALIBRATION. THE NEW CALIBRATIONS ARE AVAILABLE BEGINNING WITH CD ROM 1996 CD DISC 19 FROM GM SERVICE TECHNOLOGY GROUP.

**IMPORTANT** THERE ARE THREE METHODS FOR PROGRAMMING A PCM: 1. DIRECT PROGRAMMING. THE VEHICLE IS DIRECTLY CONNECTED VIA THE DATA LINK CONNECTOR (DLC) TO THE DEALER S TECHLINE EQUIPMENT. (T-20 PLUS, T-50 AND T-60 ONLY). VEHICLE MUST BE PRESENT.

2. REMOTE PROGRAMMING. THE NEW PROGRAM IS DOWNLOADED INTO THE DEALER'S SCAN TOOL AND THEN DOWNLOADED INTO THE VEHICLE FROM THE SCAN TOOL VIA THE DLC. TECH 2 REQUIRED. VEHICLE MUST BE PRESENT.

3. OFF-CAR PROGRAMMING. A PCM MAY BE PROGRAMMED WHILE REMOVED FROM THE VEHICLE BY USING THE OFF-BOARD PROGRAMMING ADAPTER (OBPA), P/N J-41207-B. THIS ADAPTER CAN BE CONNECTED TO EITHER THE TECHLINE TERMINAL FOR DIRECT PROGRAMMING OR TO THE SCAN TOOL FOR REMOTE PROGRAMMING. NOT NECESSARY FOR THE VEHICLE TO BE PRESENT.

REFER TO THE APPROPRIATE SERVICE MANUAL OF TECHLINE INFORMATION FOR MORE DETAILED INSTRUCTIONS.

**IMPORTANT** DO NOT ATTEMPT TO ORDER THE CALIBRATIONS FROM GMSPO. THE CALIBRATIONS ARE PROGRAMMED INTO THE VEHICLES PCM VIA A TECHLINE TOOL DEVICE.

PARTS INFORMATION APPLICATION AXLE RATIO EMISSIONS PART NUMBER CAMARO/FIREBIRD 3.08 NATIONWIDE-U.S. 16252294 CAMARO/FIREBIRD 3.08 CANADA/UNLEADED EXPORT 16252304 CAMARO/FIREBIRD 3.42 NATIONWIDE-U.S. 16252314 CAMARO/FIREBIRD 3.42 CANADA/UNLEADED EXPORT 16252324 CAMARO 3.42 JAPANESE EXPORT 16252334 FIREBIRD 3.42 EUROPEAN EXPORT 16252344

WARRANTY INFORMATION FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

LABOR DESCRIPTION TIME OPERATION J6355 ON CAR PROM REPROGRAMMING USE PUBLISHED LABOR FLASH E PROM OPERATION TIME J6352 OFF CAR PROM REPROGRAMMING USE PUBLISHED LABOR FLASH E PROM OPERATION TIME

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.