Spark Plug: Testing and Inspection

CLEANING AND INSPECTION
Clean the spark plugs as necessary using a wire brush or professional spark plug cleaner (follow manufacturer's instructions).
Inspect the electrode. (Refer to the Spark Plug Inspection Chart). Replace the spark plugs if they are worn or damaged, with spark plugs that have a "PP" suffix letter.

NOTE:
If a spark plug is removed for examination, the same spark plug must be reinstalled in the same cylinder. Cylinders No. 1 and No. 3 will use sparks plugs with a "PG" suffix. Cylinders No. 2 and No. 4 will use spark plugs with a "P" suffix. If a spark plug must be replaced, only use spark plugs with the service part number suffix letter "PP" as shown on the engine decal.