1994 Ford Ranger no air out vents but can hear it blowing

You are looking for a vacuum leak. The defalt position for the HVAC is the defroster. There are vent doors that deflect the air in the direction that you want. They are actuated by vacuum from the engine. Check under the dash for vacuum leaks. Also, on the passanger side you will see a vacuum actuator and linkage going to the HVAC. Make sure the linkage is connected.

Finally, if you start the engine, you may get lucky and hear a hissing sound from the vacuum leak. It makes it much easier to locate.

Let me know if you find it.

Joe