Need some advice on my 2002 Audi A4 Avant. The car started misfiring and when I took it in my mechanic said it needed a full tune up. He said the cause of the misfire could be a leaky gasket that was causing oil to effect the spark plugs. Ran well for a a few days after the tune up, but now misfiring again. Particularly bad on hot days. Question is, what exactly am I looking at to get the car running well again? About 78k miles on the car, so I’d like to keep it, but not sure what I’m getting into. How big is this job?
Thanks!