I recently purchased my first jeep(yes I'm a virgin) after many yrs of waiting. I had a problem with the blower resistor pack. I changed that for about 30 bucks and the AC works great. Now I noticed that a lot of hot air come from the bottom. Not from the lower vents and it's really hot. It feels like all the heat from the engine is passing through. I put the ac into the "recerculate" option or whatever that's called and the problem subsides. Is there suppose to be a cover for the bottom of the dash? or does this sound like an AC issue?