I'm reaching out to the wealth of knowledge in this forum as I have an issue with my a4 which has only come about from a recent tyre change. Since having my MOT done at audi they changed the rear tyres for new conti contact 5, I have Pirelli rossos on the front about 2mm tread left and the car has since handled awful. When ever I put the power down hard the traction control kicks in as if I have wheelspin especially coming out of a roundabout or corner, usually 2nd or 3rd gear making the car very unstable. I initially took the car back to audi to investigate and they couldn't find a problem but 1month later I can't stand it any more. I never had this issue before the change and basically wanted to know if it's a tyre issue (need 4 tyres the same) or a possible Quattro issue and a coincidence it happened at the same time.