air conditioning

[notsocool]

1996 LeSabre - when the car is started and the AC is turned on, the cool air blows out the defrost windshield vents and the floor vents. After about 5 minutes the air blows correctly out the dash vents. Any ideas?

[yogi_123rd]

It sounds like you have a weak/leaky vacuum connection.

The AC/Heater vent system works off engine vacuum. The default (i.e. no vacuum) sends air out the defroster. In the engine compartment, a rubber hose goes to a vacuum accumulator connection (small+ boxlike located on firewall down and to the left of the master cyclinder). A second plastic hose also connects to the vac accumulator and goes thru the firewall to the AC/HEATER unit. The usual problem is that the rubber vacuum hose dryrots or falls off. Check for a good connection here as you may be getting partial vacuum.