Q: Oil leaking into spark plug valve.

asked by on January 13, 2016

I have oil leaking into one of my spark plug valves. The Service Engine Soon light is also on.

Hi, this comes up often on this car. The spark pug tubes go through the valve covers on this engine due to the placement of the spark plugs. The seals that go on the valve cover to seal the tubes from the oil in the valve train tend to get old and they crack over time. When this occurs oil will get into the tube which will contaminate the spark plug wires and cause a connection issue to the plugs themselves. This will then cause a misfire which causes the engine light. The valve cover gasket and seals will need to be replaced, and it is a good idea to replace the plug wires and spark plugs though they can possibly be cleaned up and reinstalled if they are in good shape. If you are not comfortable with replacing this you should get the assistance of a mechanic, like one from YourMechanic.

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