What you will probably find is the vacuum actuator that is behind the dash, just about dead center left-right and top-bottom has a split boot and will need replaced. These were a common failure in the first few years of the 2nd Gen.
I had to replace the one in my '95. Not fun getting to it, but it was only a $20 part at the time.

Also might be a good time to replace the heater core while you are there.

 

Well I finally got around to taking the dash out and I found the problem. The actuator for the vent was broken and once replaced everything worked fine. I went ahead and changed the heater core but I'm still not getting heat properly.

Sometimes it will work great and get real hot but other times it'll only get luke warm. When the heat is working the heater core line are nice and hot but when it's blowing luke warm one side of the heater core line is hot to touch and the other one is warm but not hot. I'm thinking I might have a blend door problem or maybe the controller isn't working right. Any ideas?