[nassaubayman]

I recently bought a '67 Mustang that has in-dash A/C. No matter what position the selector is in (A/C, Fresh, Heat, Defrost), the air only blows out the bottom (heat?) vent. What do I need to do in order to fix this issue? Any insight would be greatly appreciated.

[5.0 in a 66]

One of the cables that controls the flappers that directs the air is either seized or busted. Call up NPD and order a new one.

[67stangcoupekid]

hey man im dealin with the same thing and hes right its the control cable its stuck or the flaper its self is froze up..... if you know how to work on things it shouldnt be to hard to pull the cover panel off an hit that cable with some PB blaster or something else if its just froze up ... i did that to my windows an they all work perfect again just needed some oil to break em loose

[joef21]

The problem is most likely a vacuum problem. On the 67 under dash unit, all fuctions except the air routing through the heater core is controlled by vacuum valves. I suggest you buy the aftermarket electrical/vacuum schematics. It will show you the areas to look at. If I remember right when I bought mine, I had to get a 68 versions to get the air vacuun schematics.