Skylark V6-3100 3.1L VIN M SFI (1996)
Spark Plug Wire: All Technical Service Bulletins
Ignition - Engine Miss, Updated Spark Plug Wires
File In Section: 6 - Engine
Bulletin No.: 77-64-03
Date: February, 1997
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.
Warranty Information
