1999 Oldsmobile Alero fogging up

My car fogs up as as soon as it gets a little cold outside. I have put r34a in it to make sure it had enough in it. I also put a new pressure switch on, (i beleive it has one pressure switch for high and low pressure). The problem is better, but is still pretty bad. The windshiels doesnt fog up anymore, but the other windows are very hard to see out of. If I crack open both front windows the fog will go away slowly in the front, but the rear is still solid fog. The drain isnt blocked, it will still drain out alot when I stop. Also, alot of times it will be fine, but if I stop somewhere, even for a few mintues, and I get back in to drive again, it will fog up. I can even tell its humid inside sometimes, the air is thick, seeming like the AC isnt working, but not all the time does it do this when it fogs up. Do you have any suggestions?