windshield fogs no matter what setting Climate Control is on

[Rain]

Yes, Its strange. Nearly any setting I place the climate controls on, the center windshield vent is blowing full blast. Results: patch of fog - some times inside, other times out.

Not detrimental to driving, but irritating to say the least.

I do know that my lines are acting up, as the controls are almost always sluggish to respond. Obvoius that the center vent is just not closing like it should. Really just making sure that its not supposed to ALWAYS be on.
Thanks
Rain

[c4cruiser]

Sound like you may have a small coolant leak in the heater core. Does the fog go away with full heat in defrost mode and the fans on full speed?

I get a bit of fogging with constant A/C use but I think that is due to the system removing normal humidity in the cabin and then the moisture collects inside the box when I shut the car off. Shows up when I start the car and turn the system on but goes away in a few seconds. It's worse just after high humidity outside (like rain) but it's not a problem.

Is there any smell associated with the problem? I'm not sure if the box has drain or weep holes in it that may be clogged up. Sometimes you can get mildew in there and that will cause problems. The dealer should have a spray that they put into the vents to kill mildew.

[Rain]

Yes, the fog goes away when i put the heater on the higher temps.
and
no, no odor. (not from there anyway, Im about to put a post up re: the odor from the windshield fluid)

Thanks
Rain