In the winter my '01 venture fogs up like crazy when the heater is on (floor mode). Ice will actually form on all the interior windows if it is cold enough. I have to run the defroster all the time. The floors do not seem to be wet like other people on the forum have described but I will check them. I've had my mechanic check it for heater core/cooling system leaks but they didn't find anything wrong with them.

Anyone have any ideas?
Thanks in advance.