2001 Altima. 59k miles. Runs like a dream, however it started skipping while standing at red light. I think to myself that maybe I should change the spark plugs. I pull the spark plug wire and its full of oil! I pull the second one and it too was full of oil, the last 2 were dry. I take it to the mechanic and he tells me that it would cost about $100 and told me some gasket failed. Is he right?