I just purchased a used 04 Audi A6 3.0 automatic w/ 60k miles. The second day I had it it didn't start, and they replaced the battery. Now it starts fine, but in first gear and while idling the car shakes as if its going to stall, and it shakes while accelerating. Also, it smells like its overheating but the temp gauge is fine, and the check engine light is on.
I'm thinking of exchanging the car b/c its in the frist month. It has a 2yr warranty. What do you think is the problem, and do you think its a good idea to exchange it for another vehicle given the problems already?