1988 Buick Park Avenue - Help me here....

[Dennis Peacock]

My parents gave us my mom's Buick Park Avenue. It's in really nice shape and mechanically sound. However, the A/C blows at the floor and at the windshield as if it is trying to defrost. I pressed all the button of the control board but nothing makes it change to blowing air out the normal A/C vents. I know that are things like vacuum lines under there and such and solenoids that move the flaps that channel the air.

How can I fix this where it blows the A/C our the normal forward facing vents/channels instead of it blowing out the locations for winter heat?

1988 Buick Park Avenue with all the bells and whistles. V6 engine and front-wheel drive

[Bill Huber]

I am not sure if all of the controls on that one are vacuum or not but I would say go to the Buick forum and see what they have to say.

http://www.buickforum.com/forum/

[Jeff Monson]

Dennis, The mode controls for the heater/ac system on this car are all vacuum operated. The "default" position for the mode control is defrost/heat. The first thing I'd look for is a vacuum leak under the hood. This system starts with a source vacuum on the engine (line off the throttle body), it runs to a vacuum reservoir (I will attach a pic.) That would be the first place to start, if there is vacuum to the reservoir then the problem lies after the res. if no vacuum the the problem is in the engine bay. I'd suspect a problem in the engine bay as that is most likely (broken plastic line). If the problem is under the dash you should hear a hissing noise inside the car when you move the selector for the mode position. I'll be happy to answer any questions you might have if you want to go further. 200013

[Dennis Peacock]

The reservoir is next to the power brake booster under the hood?

[Jeff Monson]

The reservoir is next to the power brake booster under the hood?

Thats what my alldata shows Dennis, let me know if its not there.

[Dick Adair]

Dennis, I had an 80 Olds with a similar problem. The actuator controlling the air deflection broke, and that vane always went to defrost. The dealer wanted $$$$$$$ to remove the dash to repair, so I figured out how to change the air flow, and every fall and spring I changed it. It was a nuisance but I never did repair it. Good luck with yours.

[Dennis Peacock]

Jeff,
Thanks.....I went back and looked again after studying your drawing. I see it and am tracking down the lines as time / work permits.

[Dennis Peacock]

OK....thanks Jeff..!!!!!

Fixed it.....vacuum hose was the problem. :D