Asked in
Air Conditioning and Coolant
Ford Explorer Limited
Car Heaters

Why would the ac blow warm air out defroster when accelerating on a 1986 Lincoln continental?


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Wiki User
September 12, 2007 12:17AM

You have a bad vacuum reservoir or leaking vacuum line. Vacuum is usedd to control the air duct doors in your system and when you accelerate, the vacuum supply is greatly reduced...causing the duct doors to "default" to the defrost position.