Spark Plug Inspection

Burned or worn electrodes may be caused by: 

• Advanced ignition timing
• Loose spark plug
• Plug heat range too hot
• Insufficient cooling

Fouled plug may be caused by: 

• 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 coil or ignition wires
  Fig 1: Inspecting Electrodes & Ceramic Insulator

  Courtesy of AMERICAN HONDA MOTOR CO., INC.

'98-99 models: 

• Adjust the gap with a suitable gapping tool.

  Electrode Gap 

  1. Standard (New):  1.0-1.1 mm (0.039-0.043 in.)
• Replace the plug if the center electrode is rounded (A).

  Spark Plugs 

  1. NGK:  ZFR5F-11
  2. DENSO:  KJ16CR-L11
  Fig 2: Checking Electrode Gap

  Courtesy of AMERICAN HONDA MOTOR CO., INC.

  '00-02 models: 

• Replace the spark plug if the gap is out of specification.

  Electrode Gap 

  1. Standard (New):  1.0-1.1 mm (0.039-0.043 in.)
  2. Service Limit:  1.3 mm (0.05 in.)
• Replace the plug if the center electrode is rounded (A).

  Spark Plugs 

  1. NGK:  PZFR5F-11
  2. DENSO:  PKJ16CR-L11