My 85 Park Ave seems to blow hot air whenever Im driving. It blows from the bottow of the dash and from the vents if I turn the AC on which dont seem to work either. Its 95 degrees here in GA and its driving me crazy. Can anyone give me a clue as to where to start. Hot airs just blows hotter and hotter the more I drive. Especially on the interstate. The heater will blow if I trun it on but it does not have to be on to feel hot air comeing from from it. What could be the problem? Thanks.