Hi Noticed my late 01 A4 2 ltr misfiring on friday last. Assumed coil or HT lead problem and decided to drop it into my local Audi dealer, as I also had a broken brake sensor, and to my horror they tell me its cylinder 4 damaged. Loss of compression and i need to get the head repaired and new seals,valve etc. Has anyone else had this problem. The car is well outside warranty and Im being quoted 3000 euros for the repair. 1000 is just on labour costs alone Car only has 60k and is always serviced reg... Does this cost sound right to you ??