ENGINE RUNS ROUGH, LACK OF POWER, KNOCK NOISE. Buick Park Avenue 1998

SUBJECT: ENGINE RUNS ROUGH, LACK OF POWER, KNOCK NOISE, MIL ILLUMINATED (REPLACE SPARK PLUGS AND REFLASH PCM)

MODELS: 1998 BUICK LESABRE, PARK AVENUE 1998 OLDSMOBILE EIGHTY EIGHT, LS, LSS, REGENCY 1998 PONTIAC BONNEVILLE WITH 3.8L ENGINE (VIN K - RPO L36)

CONDITION:

SOME OWNERS MAY COMMENT THAT THE ENGINE RUNS ROUGH, HAS LACK OF POWER, HAS A KNOCK NOISE, AND/OR THE MIL (MALFUNCTION INDICATOR LIGHT) IS ILLUMINATED. THE SERVICE TECHNICIAN MAY DETERMINE THAT DTC DIAGNOSTIC TROUBLE CODE) P0300 IS STORED IN THE PCM (POWERTRAIN CONTROL MODULE). THE SERVICE TECHNICIAN FURTHER DETERMINES THAT THE AFFECTED CYLINDERS HAVE ERODED SPARK PLUG ELECTRODES.

CAUSE:

THE ESC (ELECTRONIC SPARK CONTROL) CALIBRATION WITHIN THE PCM MAY NOT CONTROL THE SPARK TIMING PROPERLY RESULTING IN PRE-IGNITION. THE PRE-IGNITION MAY CAUSE THE SPARK PLUG ELECTRODES TO ERODE AND PRODUCE THE CUSTOMER CONCERN.

CORRECTION:

1. INSTALL A SCAN TOOL AND VERIFY DTC P0300 (ENGINE MISFIRE DETECTED) IS SET.

**2. NOTE THE CALIBRATION ID CURRENTLY IN THE PCM.**

3. REMOVE ALL SIX SPARK PLUGS AND INSPECT FOR ERODED ELECTRODES.

4. IF NO SPARK PLUG ELECTRODES ARE ERODED, THEN REINSTALL THE ORIGINAL SPARK PLUGS AND CONTINUE DIAGNOSTICS USING THE P0300 DIAGNOSTIC CHART IN THE APPROPRIATE SERVICE REPAIR MANUAL. AFTER ALL REPAIRS ARE COMPLETED, FLASH THE PCM WITH THE CALIBRATION LISTED UNDER THE PARTS HEADING IN THIS BULLETIN IF DIFFERENT THAN THE CURRENT CALIBRATION AS NOTED IN STEP 2.

5. IF A SPARK PLUG ELECTRODE IS ERODED, THEN INSTALL NEW SPARK PLUGS AND FLASH THE PCM WITH THE CALIBRATION LISTED UNDER THE PARTS HEADING IN THIS BULLETIN IF DIFFERENT THAN THE CURRENT CALIBRATION AS NOTED IN STEP 2.

PARTS INFORMATION

SPARK PLUG: SPO P/N: 25161444 AC P/N: 41-921

THE NEW CALIBRATIONS ARE AVAILABLE FOR TECHLINE TOOLS STARTING WITH THE 1997 CD 24 RELEASE FROM GM SERVICE TECHNOLOGY GROUP (STG).

DO NOT ATTEMPT TO ORDER THE CALIBRATION NUMBERS FROM GMSPO. THE CALIBRATIONS ARE PROGRAMMED INTO THE VEHICLE'S PCM VIA A TECHLINE TOOL DEVICE.

ENGINE AXLE EMISSION CALIBRATION MAKE/MODEL CODE RATIO STANDARDS ID BUICK LESABRE K 2.86 USA-FED CANADA 09357164 LESABRE K 2.86 CALIFORNIA TLEV 09357174 LESABRE K 2.86 UNLEADED EXPORT 09357184 LESABRE K 3.05 USA-FED CANADA 09357194 LESABRE K 3.05 CALIFORNIA TLEV 09357204 LESABRE K 3.05 UNLEADED EXPORT 09357214 PARK AVE K 3.05 USA-FED CANADA 09357114 PARK AVE K 3.05 CALIFORNIA TLEV 09357124 PARK AVE K 3.05 UNLEADED EXPORT 09357134

OLDSMOBILE 88,LS K 2.86 USA-FED CANADA P225 TIRES 09357144 88,LS K 2.86 CALIFORNIA TLEV P225 TIRES 09357154 88,LS,REGENCY K 2.86 USA-FED CANADA P205/P215 TIRES 09357164 88,LS,REGENCY K 2.86 CALIFORNIA TLEV P205/P215 TIRES 09357174 88,LS,REGENCY K 2.86 UNLEADED EXPORT P205/P215 TIRES 09357184 LSS K 3.05 USA-FED CANADA 09357194 LSS K 3.05 CALIFORNIA TLEV 09357204 LSS K 3.05 UNLEADED EXPORT 09357214

PONTIAC BONNEVILLE K 2.86 USA-FED + CANADA 09357164 BONNEVILLE K 2.86 CALIFORNIA TLEV 09357174 BONNEVILLE K 2.86 UNLEADED EXPORT 09357184 BONNEVILLE K 3.05 USA-FED + CANADA 09357194 BONNEVILLE K 3.05 CALIFORNIA TLEV 09357204 BONNEVILLE K 3.05 UNLEADED EXPORT 09357214

WARRANTY INFORMATION FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

LABOR OPERATION DESCRIPTION LABOR TIME J6355 PROM- REPROGRAMMING USE PUBLISHED LABOR ON CAR OPERATION TIME

J4226 SPARK PLUG - REPLACE USE PUBLISHED LABOR OPERATION TIME

J4217 SPARK PLUG - DIAGNOSTICS USE PUBLISHED LABOR WITHOUT REPLACEMENT 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.