my wifes 97' olds cutlass supreme ac stopped working at the dash vents.it will blow out of the top dash and lower dash.but not in the vents that blow to your face. any ideas? thanks gary

Check the vacuum lines on the intake mainfold, one of them supply the valves behind the dash.

Definitely vacuum related. If all is well in the engine compartment, something is either loose, leaking, or broken in the lines into/from the heater/ac control panel.

thanks, i guess i'll start pulling things apart this weekend.gary

When my wife's olds did that, it was a vacuum leak in the seam of the plastic vacuum tank.

dean where is the tank and what does it look like? color ,size. thanks gary

Gary. when you switch to dash vent. put your hand up under the dash and see if you feel any air. You may have a duct that fell off. This happened to my truck.

found the problem on the olds.somehow some papers had gotten in the lower vents and blocked the ac from blowing.go figure.gary