For 1990-2009 cars

# ENGINE MISS (REPLACE SPARK PLUG WIRE & IGNITION COIL)

#### SUBJECT: ENGINE MISS (REPLACE SPARK PLUG WIRE AND IGNITION COIL)

#### MODELS: 1994-96 BUICK SKYLARK 1994-96 CHEVROLET BERETTA, CORSICA 1994-96 OLDSMOBILE ACHIEVA 1994-96 PONTIAC GRAND AM WITH 3100 V6 ENGINE (VIN M - RPO L82)

#### CONDITION:

SOME OWNERS MAY EXPERIENCE AN INTERMITTENT ENGINE MISS. ADDITIONALLY, A CONTINUOUS LOSS OF POWER MAY DEVELOP DUE TO AN ENGINE MISS. TYPICALLY, THIS CONDITION OCCURS AFTER 18-24 MONTHS OF SERVICE.

#### CAUSE:

FOR 1994 START OF PRODUCTION A NEW SPARK PLUG WIRE WAS USED WHICH HAD A DIFFERENT TERMINAL END AT THE COIL TOWER. UNDER SUFFICIENT VIBRATIONAL FORCES, THE WIRE TERMINAL CAN ROCK ON THE SECONDARY COIL TOWER. WITH TIME, MICRO-ARCING WILL OCCUR BETWEEN THE SPARK PLUG WIRE TERMINAL END AND THE IGNITION COIL POST. THE MICRO-ARCING WILL ACCELERATE CORROSION AND EROSION BETWEEN THE TWO SURFACES.

#### CORRECTION:

THOROUGH INVESTIGATION HAS REVEALED THAT CYLINDERS 2 AND 4 HAVE THE GREATEST PROBABILITY FOR MICRO-ARCING. TO DETERMINE IF THE ENGINE MISS IS DUE TO MICRO-ARCING, REMOVE THE SPARK PLUG WIRES AT THE IGNITION COIL AND INSPECT. IF MICRO-ARCING HAS OCCURRED, THE TERMINAL END WILL BE CORRODED AND BLACK IN COLOR. IF THIS HAS OCCURRED, REPLACE THE SPARK PLUG WIRE. ALSO, INSPECT THE IGNITION COIL TOWERS FOR PITTING AND/OR FRETTING. IF THE IGNITION COIL TOWER IS HEAVILY PITTED/ REPLACE THE IGNITION COIL. THE SPARK PLUG WIRE TERMINAL ENDS HAVE BEEN REDESIGNED TO ELIMINATE THE POTENTIAL FOR FRETTING OR PITTING TO OCCUR.

PARTS INFORMATION

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

PART NUMBER DESCRIPTION QTY

12096446 CYLINDER #1 PLUG WIRE, 1994-96 1 12096411 CYLINDER #2 PLUG WIRE, 1994-96 1 12096428 CYLINDER #3 PLUG WIRE, 1994-96 1 12096412 CYLINDER #4 40" SPARK PLUG WIRE, 1994 L 1 12096447 CYLINDER #4 32" SPARK PLUG WIRE, 1994-96 1 12096427 CYLINDER #5 18" SPARK PLUG WIRE, 1994 L 1 12192003 CYLINDER #5 20" SPARK PLUG WIRE, 1994-96 1

12096412 CYLINDER #6 40" SPARK PLUG WIRE, 1994 L 1 12096447 CYLINDER #6 32" WIRE, 1994-96 L 1 10472401 IGNITION COIL 1994-96 AS REQUIRED

WARRANTY INFORMATION FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

LABOR CODE: J4206 WIRES, SPARK PLUG-REPLACE LABOR TIME: USE PUBLISHED LABOR TIME.

LABOR TIME: J4345 COIL, ELECTRONIC IGNITION CONTROL-REPLACE LABOR TIME: USE PUBLISHED LABOR 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.

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