Hi all, I hope the Thanksgiving week has been a good one. I spent a little bit of time continuing to work through the list of "things" the '97 firebird needs as I bring it back to life.

I'm up to an HVAC question. I've searched the archives and I don't "think" it is the main valve / line coming in from the engine compartment. The vent selector blows correctly on some selections like 'vent' or 'defrost' but fails to do anything but floor on the a/c options. Behind the switch I hear the continual hiss of vacuum when it is failing to shift the vents correctly.

My thought is that this is a selector switch problem since some vent controls are working and it's not all defaulting to the dash. But, thoughts welcome on this for sure before I start exploring around too much on my back on the passenger side floor.

Thanks all.

 

Sounds like it might be a problem with an actuator, or the hose is off the control assembly. See if this diagram from Shoebox helps locate the problem:

http://shbox.com/1/hvac_vacuum.jpg

 

Thanks for the help on this, I appreciate it. I'm hoping this doesn't turn into the nightmare that working on the suburban was. Fun times those were:



The dog food holding up the steering column still makes me chuckle. Adapt and overcome?

 

Do you have a copy of the factory service manual? Should show steps necessary to access the back of the HVAC controls.

Free download. Only 1996 available but should be virtually identical to 1997.

https://www.mediafire.com/?40mfgeoe4ctti

 

Thanks for that, yeah I have it loaded up and I'm about to go through it.