TheA/C Line (metal hose) that comes off the firewall and travels along the passanger fender,was completely covered in thick white frost (maybe 1/8"-1/4" thick). I opened the hood to have a look, after the a/c fan stopped blowing inside the car. I could still feel cold air, but nothing was circulating. Any thoughts?

2004 M6 2.3 ATX[/align]

 

Have you been using your ac for a long time than possible shut the car off so it cools, than start the car up and blast the ac again?Was thison a fairly warm day? If so it may be condinsation that has built up in the line. Then when you started the ac up for the second time it froze the water and sealed off the line. Or you may have a small crack in the line and be leaking freon.

 

Was driving the car at highway speeds for 1/2 hr on a warm (85) day.

 

One possibility is low freon. Another is if you had a majority of the vents closed. Anyone with other thoughts?

David

 

Recently replaced a not functioning ambient air temp sensor. Have not had a repeat of theproblem. Now I'm wondering if that sensor has an effect on the a/c ventilation system? Maybe sends some signal to the computer to control a/c temp changes? Any thoughts out there?