a week ago, i was driving my audi 2.0t pretty hard, taking it up to 5300 rpm's. Over the next couple of days, i noticed that the engine soundsa little rougher, especially around 1500-1800 rpm's. Yesterday, my dad drove the car and i noticed as he was pulling out that the left tailpipe was shaking more than the right and the noise seemed to come from there. Any ideas to what it could be.

 

could be alot of things if its a constant noise that always comes back take it to the dealer. if your cars under warranty.