Operation CHARM: Car repair manuals for everyone.

Wet Oily Deposits

Symptoms: Electrodes coated with excessive wet fuel or oil.

Possible Causes:
- In older engines, wet fouling can be caused by worn rings or excessive cylinder wear.

- In new or recently overhauled engines, fouling may occur before normal oil control is achieved. Break-in fouled spark plugs can be usually be cleaned and installed.