Ignition Coil and Spark Plug Removal, Installation, and Inspection: Inspection

• Do not adjust the spark plug gap, because the electrode may be damaged.
• Replace the spark plug according to the maintenance schedule.
• Replace the spark plug with a spark plug from another cylinder if abnormality is suspected, and confirm the change in circumstances.
• Measure the iridium plug gap with the plug gap gauge (wire type).
• Do not use a wire brush or scrape the iridium electrode since this will damage the electrode.

1. Inspect the electrodes and the ceramic insulator.

• Burned or worn electrodes may be caused by these conditions:
• • Advanced ignition timing
  • Loose spark plug
  • Plug heat range too hot
  • Insufficient cooling
• Fouled plugs may be caused by these conditions:
• • Retarded ignition timing
  • Oil in combustion chamber
  • Incorrect spark plug gap
  • Plug heat range too cold
  • Excessive idling/low speed running
  • Clogged air cleaner element
  • Deteriorated ignition coils