Cylinder 5 misfire- changed plug found oil on plug other than that plug looked like normal wear. Whats the cause and will the oil burn off. Since the new plug was placed in C5 it seems to be running ok. Something to worry about?

Spark plugs / wires below valve cover? ..... Spark plugs / wires in middle of valve cover? Yeah - it makes a difference.

That’s a first! Ok - DURATEC engine - Valve cover gasket is leaking oil into the spark plug well .. Valve cover gaskets will need to be replaced.

The valve cover gaskets also seal out the engine oil from the spark plug tubes.. That is where the oil on the spark plug is coming from.. Oil ponding in spark plug tube(s) ‘WILL’ eventually lead to another misfire!

Prices vary from shop to shop and zip codes - recommend contacting local auto repair facility. You can try tightening the valve cover bolts down a bit - just don’t ‘over tighten’ em. Good luck with it!

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