I have a 1999 A6 2.8 Quattro and I am having an air conditioning problem. It works but the fan cuts in and out. When its out I am still getting cold air, just not at any velocity. What could this be? Thanks for any help!

 

Failed blower motor or ac control head. Possibly a blower motor control module. Not sure if it was one piece or a serpate module for that model and year.

 

Check your climate control diagnostics.

http://www.audiworld.com/tech/int5.shtml