My a/c runs super cold but it jumps from the dash vents to the floor to the defrost vents on its own, any ideas?

 

If you've got an older model year - suggest that there are vacuum leaks in the HVAC controls. If so, you will notice the changes whenever the engine is under load.

Not sure how the newer model years control the dampers.

 

It Does happen under "load" like you said, so what do I need to do? I have a 95' XLT.

 

There should be 3 vacuum-actuated motors - the floor/vent, floor/defrost, and fresh air / recirc - controlled by the selection panel. There should also be a vacuum supply to the panel from the engine. IIRC, the default (no-vacuum) position for these motors is to the floor and fresh air.

The fresh air / recirc motor should be in the engine compartment, tucked up against the firewall near the passenger-side fender. This is where I had a hose failure, I suppose due to being exposed to heat. The other two motors can be accessed by removing the glove box - a pretty simple operation.

If a visual inspection turns up nothing - a hand-operated vacuum pump is a great tool for testing hoses and vacuum motors - just a matter of going through the motions to find where the leak is.

One other thought - if the vacuum reservoir system has failed, this can also cause the same problems with the HVAC and also the cruise control should it be vacuum-operated (my model year is). My reservoir is a tomato juice can-looking thing sitting on the passenger-side fenderwell in the engine compartment.

Not sure if Ford uses vacuum check valves, but I've had problems with these holding on GM vehicles. Unfortunately, I have not been able to locate my vacuum schematic for the HVAC system.

 

That helps a lot.