What does it mean when I pull the spark plug wires off of the spark plug and there is oil on the tip of the spark plug wire? It's almost like it's getting blow by past the plugs, the threads on the spark plugs are always oily when I pull them out. My main questions other than the first one is How much longer can I drive it like this for? If I keep driving it like this will it permanently affect my motor? How much power could I be losing due to this?