Spark Plug: Adjustment

Clean the spark plugs using a wire brush.

Clean and remove the carbon or oxide deposits.

But do not wear away ceramic insulator.

If deposits are too stubborn, replace the plugs.

After cleaning the spark plugs, correct the spark plug gap using a gap gauge.

NOTE: Do not use a plug cleaner because the spark plugs are applied with platinum tip.

Spark plug gap L:

1.0 - 1.1 mm (0.039 - 0.043 in)

Fig 1: Identifying Spark Plug Gap L

Courtesy of SUBARU OF AMERICA, INC.

NOTE: Replace with a new spark plug if the area (A) is worn to "ball" shape.