GM Service Manual Online
For 1990-2009 cars only
  1. Inspect the spark plug wiring for the following:
  2. • Correct routing
    • Clean and tight connections
    • Cuts
    • Burns
    • Chafing
    • Damage
  3. Reroute or replace the wire(s) as necessary.
  4. With the engine running, inspect for any arcing. Replace as necessary.
  5. With the engine OFF, measure the resistance of each suspect wire. If the resistance is greater than 25,000 ohms, replace the wire.