Visual Inspection

Inspect the following items:
- If any of the following malfunctions are indicated, replace the spark plug.
  - Insulator breakage
  - Worn electrode
  - Damaged gasket
  - Badly burned insulator (sparking side)
    
    Fig 1: Inspecting Spark Plug, Insulator Breakage, Worn Electrode And Damaged Gasket
    Courtesy of MAZDA MOTORS CORP.