06 A6 3.2 V6. 132,000 miles. Very dirty around driver side valve cover. Very clean on the other one. I'm doing this work for a friend and he states the car uses a quart of oil every 1200 to 1500 miles. No smoke or smell. Can I or should I just re-torque the valve cover bolts? Can anyone tell me what that torque spec. is on those bolts? And in what order should I torque those bolts? Thanks in advance.