[crawdad]

I had a problem similar to this. If I remember correctly there is a flapper door that is opened and closed depending on what your selector is set to. It is controled by a vacuum pod that opens and closes it. In my case, the vacuum line had come loose and all I had to do what put it back on. Yours could be something similar, not allowing the door to close or open all the way. I think the vacuum pod is behind the glove compartment or underneath the dash, right in the middle, I forget. You may have to take off some of the duct work, but you'll see it if you look. Hope I haven't confused you too much.