GM Service Manual Online
For 1990-2009 cars only

Spark plug wire integrity is vital for proper engine operation. A thorough inspection is necessary to identify conditions that may affect engine operation. Visually and physically inspect the following:

    • Inspect the routing of the wires. Refer to Spark Plug Wire Replacement . Improper routing can cause cross firing.
    • Inspect each wire for any signs of cracks, burns, or splits in the wire.
    • Inspect each wire end for damage, corrosion, or moisture contamination at the terminal.
    • Inspect each boot for signs of tears, piercing, arc through, or carbon tracking.

If corrosion, carbon tracking, moisture, or arcing are found on the spark plug wire terminal or boot, both the wire and the component that is connected to the wire should be replaced. Refer to Spark Plug Wire Replacement and Ignition Coil Replacement and/or Spark Plug Replacement .