I have a 03
A4 with the 1.8T. Well the car just hit 50k miles. One day when i drove home from work i noticed a smell. OIL! Well i took the cover off and sure enough i have a seeping valve cover. I also noticed that my antifreeze had started to disapear. About a quarter of an inch every two weeks. I have checked and double check for leaks and cant find any. For the finale today when i was looking at the engine looking for the leak after driving home from work i noticed smoke coming from around my O2 sensor. Now i work at a NAPA auto parts store and i have never heard of an O2 sensor smoking. Any ideas about any of this? Anything would be a help at this point.