Help! Whiletraveling at 70 mph or so inmy 02 A4 Quattro, I let up on the peddle for a second because fo traffic. When I started to accel again I heard a thunk, knock I believe in my tranny. It performed fine except that noise. After serveral trys hoping it would stop I discovered that it happens at any speed. I all I have to do is just let up on the peddle then press it again. Does anyone have idea? I had my tranny fluids changed. Am I at the early stages of some major repairs or what???????????