I've always been annoyed with this. Anyways, it's now gone. The cam shaft tensioners were the problem and have been replaced. But you don't want to know how much this fix costed. It would bring tears to your eyes. the car is a 1999.5 quattro. But it was the last annoying thing about the car. Now it's mint and runs like a champ. It's been mentioned to me that the problem occurred due to poor servicing of the vehicle while under Audi's care program. Anyways, long story short is that I will now always follow my old rules if I'm keeping the car for the long haul regardless of what these sh!tty manufacturers are saying about extended maintanance BS intevals. Just have to find some nice OEM 17" wheels for her and all will be happy !!! So if you have a set, let me know.....................