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Home >> Mitsubishi >> 2003 >> Diamante LS >> Repair and Diagnosis >> Engine Performance >> Ignition System >> On-Vehicle Service >> Spark Plug Check And Cleaning
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Spark Plug Check And Cleaning

  1. Remove the engine cover and intake manifold plenum. Refer to INTAKE & EXHAUST .
  2. Remove the spark plug cables.
    CAUTION: When pulling off the spark plug cable from the plug always hold the cable cap, not the cable.
  3. Remove the spark plugs.
  4. Check for a burned out electrode or damaged insulator. Check for even burning.
  5. Remove carbon deposits with a plug cleaner. Remove sand from the plug threads with compressed air.
    CAUTION: Cleaning a platinum spark plug may damage the platinum tip. If carbon deposits must be removed use a plug cleaner and complete cleaning within 20 seconds. Do not use a wire brush.
  6. Use a plug gap gauge to check that the plug gap is within the standard value range. Replace the spark plug if the limit is exceeded.
    1. Standard value: 1.0-1.1 mm (.039-.043 in.) 
    Fig 1: Checking Spark Plug Gap
    G01905770Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
  7. Clean the engine plug holes.
    CAUTION: Use care not to allow foreign matter in cylinders.
  8. Install the spark plugs.
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