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 accurately identify conditions that may affect engine operation. Inspect for the following conditions:

  1. Correct routing of the spark plug wires, Incorrect routing may cause cross firing.
  2. Any signs of cracks or splits in the wires.
  3. Inspect each boot for any of the following conditions:
  4. • Tearing
    • Piercing
    • Arcing
    • Carbon tracking
    • Corroded terminal

If corrosion, carbon tracking or arcing are indicated on a spark plug wire boot or terminal, replace the wire and the component connected to the wire.