Last year I had it into the shop for some unrelated work and I had them fix a broken fan control switch on the dash that had just come off. They fixed it and put it all back together and when I picked it up it worked fine. But as it was a rainy humid day I left it on defogger and drove home. That was just before we moved in Nov and it was garaged after that so I never noticed the issue. Now no matter what location you choose for your air (feet, face, etc) it will ONLY blow thru the defogger. The temperature controls seem to work ok, but you can't switch the location of the airflow. What the hell is going on here and how do I 'reset' it so it behaves normally?

thanks

 

What year? The 67-68’s were vacuume operated and the 65-66 were a manual cable.

 

69, and yeah I'm pretty sure it's a vacuum system, I've had the dash apart before and you can see all the little tubes connecting to the dash unit

 

Sounds like you're chasing a vacuum issue which oughta be a hoot.

I redid all of my vacuum hoses on my 67 and got everything working perfectly and once it was working it was wonderful but it was a bit of a pain in the butt. You will definitely want to get the factory diagrams to tackle that job.