1997 Dodge Ram

Air Conditioning problem
1997 Dodge Ram V8 Two Wheel Drive Automatic 162000 miles

On my 1997 Dodge Ram, the blower mode switch does not change the vents the air somes through. When I turn the fan on it only blows through the top of the dash (defrost vent) and the floor vents. It will not blow through the dash vents no matter what setting it is on. It only blows through the defrost and floor vents at the same time, all the time. Any clue why this is?
March 20, 2010.

In this case, you are looking for a vacuum leak. The vent doors are actuated by vacuum. If there is a leak, it will stay in a defalt mode (defrost / floor). Check under the dash for leaks. With the engine running, you may hear a hissing.

Let me know what you find.