air conditioner won't stay blowing out dash on 1997 Cadillac Seville

air won't stay blowing out of dash vents. It will blow on floor, defroster and dash but won't stay on dash

Asked by for the 1997 Cadillac Seville
There is a problem with the blend door function. It sounds like a vacuum leak in the actuator. A qualified GM service facility needs to take a look at it.
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