Oil leaking onto the spark plugs generally means that a valve-cover gasket has failed. Over time, these contract and get hard before allowing oil through. On a V-type engine, the leak shows up on the garage floor or driveway, but four-cylinder engines show the leak on the spark plugs.Continue Reading
To fix the problem, the owner just needs a new kit for a valve-cover gasket, a spray can of brake cleaner and a tube of RTV sealant, or room temperature vulcanizing sealant. A torque wrench, plastic putty knife and metric sockets help, as does a soft-faced mallet.
Tapping around the valve cover with the mallet helps to loosen it. Metal tools can damage the cylinder head, making the job much more onerous. After taking the cover off the compartment, the next step is to clean any pooled oil out with a rag on a screwdriver. After replacing any non-functioning spark plugs, the next step is to take out the bolts holding down the valve cover and to remove the cover. Now the gasket just peels off, and after using brake cleaner to clean the valve cover and gasket mating spots, it's time to put new RTV on and put the new gasket on. Snugging the valve-cover belts is the last step before reinstalling all hoses, cables, electrical connectors and parts of the ignition.Learn more about Car Parts & Maintenance