Foggy windows

The windows on my 2001 Chevrolet Cavalier fog/freeze up after driving 5 or so miles on cold cloudy days or at night. They clear up after the vechicle sets over night. I have dried the interior of the car out so that is not the issue. The higher speed you run the fan at on defrost the worse it gets—side and back windows. Any ideas what is going on here? thanks

It sounds like a leaking heater core. Are you losing coolant? Do you get antifreeze odor in the car?

No I am not losing coolant. No antifreeze odor in the car.

run your ac with the defroster with fresh air setting…that should help.

There’s moisture in the car somewhere. If you are running the heat on “recycle” switch to fresh air. You said you dried out the interior. Did it get wet somehow? If so there is probably still water in the padding under the carpet, or somewhere else you haven’t noticed. How about the trunk? Is there water in the spare tire well? Another possibility is a clogged evaporator drain hose, which may allow water to remain trapped in the HVAC system.

Do the windows clear if you run the AC with the heat? They should, and the AC compressor should come on whenever you use the defroster, to dry the air.

thanks for the reply. The windows do not clear up when running the AC with the heat. I recently purchased this vehicle for my daughter. The dealer felt it was doing it because they shampooed the carpets before I picked it up. But I have put a lot of time into getting the carpet dryed out(heated garages with fans blowing into car). When you talk about running the heat on the recycle switch to fresh air-- I do not see a switch on the controls to do this. Carpet in trunk is not wet or no water in the spare tire well. Should the air be cold when the AC is on in the defroster mode? It currently does not get cold even with the control over on the coldest setting. thanks again

thanks for the reply. I have tried that with no luck—I do not see a fresh air setting. But I have pushed the AC button with the defroster on with no luck.

By “fresh air” they mean that you are not using recirculation. There’s not usually a special button for fresh air - just turn off the recirc button (usually has a car on it with an arrow going in a loop). If recirc is off, you’re getting fresh air (mostly).

Yes, the AC should be cold whenever it’s at a COLD setting regardless of where you’re directing the air. Sounds like the AC is busted, but that only means you don’t have a way to clear the windows. You’d like to think the windows shouldnt do this, but my truck has always done it. The only way I can ever fix it is to run the AC with cold air right onto the windows (even when it’s 10 degrees outside!). My truck is dry inside as well… I’ve always thought it’s because my windshield is old or I used too much “defogger” stuff on it once.

The outside temperatures have been from -20 F to +20 F. Does the air conditioning compressor engage at those temperatures on a 2001 Cavalier? I have a 2004 Grand Prix that states the air conditioning compressor will be engaged unless the outside temperature is 40 degrees F or below.

No recirc button on a 2001 Cavalier. Even if the AC compressor is not working the windows should not be fogging up. Correct or not?

Well, does the A/C work at all? If the A/C is selected, does the compressor turn under the hood? How about in defroster mode?