An issue cropped up with my 93 a few months ago. Haven't had time to do any diagnosis. I can no longer select where the air comes out, its stuck on heat/defrost, the default on most cars I believe. What is the more likely place to start to look? Up in the controls on the dash, or down at the heater box? I had the dash setup apart last summer to refinish the panel because of 93 sticky interior issues. It worked with no issues for months and just stopped one day.

Thanks

 

Check for a loose connection in the back of the HVAC unit. If you took it apart to refinish the panel, there is a high probability that a wire or connection came loose.

 

Good point, that's the first place to check. I have to fiddle with my headunit mounting so that will be a perfect time to check.