Air Vent Problem

[Digiko37]

My friend has a 1999 Saab 9-3. When turning on a/c or heater it works fine for about 30 minutes then the air seems to stop coming out the vents gradually until none seems to flow at all. You can still hear the air blowing in the dash but cant feel the air at the defrost, top air vents or bottom vents. Maybe hours later or the next day it works fine again. Any suggestions?

[05aero]

I had a similar problem on my wifes 1999 9 3, the alternator wasn't putting out enough voltage and it would shut down non-essential items like AC and radio. Have the alternator checked to start

[mbunakeith]

sounds like your evaprator is freezing up. get the freon recharged or have a qualified person test your anti-freeze switch (on the evaporator).