GM / General Motors: 92 Buick Park Ave Heater Control Air from Defroster and floor all the time

There are actuators that cotrol the airflow in the heater core box/
electrical / mechanical. they may need to be replaced



On Mon, 17 Nov 2003 20:20:43 -0500, "Mastermech"
<net> wrote:
 

I had the exact same problem with my '94 PA. I checked all of the
vacuum hoses also, but it didn't solve the problem. Then, when I was
changing the Master cylinder, I noticed the vacuum line that goes into
the firewall to control the heater controls was partially connected
(vacuum leak). The car never ran rough. I reconnected the vacuum line,
and the controls started working again.

I also found this link to help out. I actually went to an auto-recycler
and pulled out the vacuum manifold from another PA just in case. Never
needed it. I have since sold the car. If you determine that the vacuum
manifold on your PA is bad and want the one I have, let me know.

http://www.imcool.com/articles/aircondition/fix_vacuum_line.htm

Bill

Mastermech wrote: 

Thanks for the link William.
That looks indeed like it may be my trouble, I will try to get in there
and take a look this weekend and post back.