So I just bought my Audi used and this might sound crazy, but I just realized that there is a piece of rubber tubing missing. When you look behind the alternator in this pic you a blue "thing" and behind that is a square metal thing with a circular inlet or outlet with a rubber elbow connected to it. This is the piece my car is missing. Please don't flame or bash me but i'm having a tough time figuring out what that is and what part number I need. Thanks guys.