This may be a cause... My wife's 95 contour had to have the vacuum temp settings control unit replace 2 times. If you are constantly changing settings it really blows the valves in the climate control center...
Just a thought.
My ac blows only in the defroster and not any of the other vents i have 98 ford windstar 3.8 v6
Check for vacuum leak either under hood or under dash Check for bad vacuum actuator under dash Defrost is the default setting
If it blows only out the defroster vents : then check for Vaccume leak Rick ASE L-1 Master TransMichigan.com
The 1984 Buick uses vacuum lines to change air flow from defroster to ac vents. Check the entire vacuum system for leaks.
some thing is probley cloging the vents take it appart and ckeck.
Dont know what the problem is but i can tell you its a vacuum leak . the vents are vacuum operated and require air pressure to change between the vents and floor. the defroster is default setting you may have a vacuum line that has come undone but all i know is its somewhere under the dash.
your switch cable might be broke you will have to remove your dash
If air blows from defroster only, the vacuum line to the blend door may be broken. You can access most of it under the hood.
Because it's not a defroster button! It's just the symbol for ventilating the air into the car. It shoudln't be called a defroster since defrosting is meant by heating up the coils that you see at the back of the car. I'm pretty no car has wires in the front!
I had the same problem and then the fan quit blowing. It was all controlled by the automatic temperature controller. If I remember correctly it was referred to as a ATC chip. I purchased the chip on line from a used parts outfit somewhere in the north for about $50.00. It is pretty easy to install. It's located on the firewall on passenger side behind a heather hose
It sounds like there is a vacuum leak. Check under the dash for any small hoses not attached and then look under the hood for any. The hoses should be small and grey or black.
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