Car Fogging Troubles

Rothrandir

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In cold weather, my car always develops a fog on the inside of all windows, and is extremely difficult to get rid of. In super cold weather, like we've been having, that fog turns into ice.

While a certain amount of fogging might be expected from time to time, I've never seen anything like I get in mine.
I'll drive to the store, come back outside, and see that all my windows have a thin layer of ice, whereas the rest of the cars in the lot do not.

Anything I can put in there to maybe suck up some moisture? There seems to be so much of it that I'm not sure how I'd absorb it all. I wonder where it's coming from?
 
You might have a pinhole leak in your heater core. The tiny bit of moisture it releases and evaporates ends up condensing on your windshield because it is the coldest.

My car had a similar problem. It turned out to be a slightly loose hose clamp at the heater core.

If that is your problem you should be able to smell it. It might only be strong when you first turn on the heat.

Greg
 
Cold winter air is dry by nature (cold air holds little moisture) A solution for you might be to "crack" the windows open a little bit 3/16 - 1/4 in. while driving. Additionally keep your interior ventilation on. Keep your defrost off if the vehicle has not warmed up yet. The moisture from you breath condensing on the cold windshield will be bad for forward vision, IMHO. For best results ,Clean your windows every few weeks with an alcohol based solvent, use Plenty of paper towels (some folks recommend newspaper, crumpled up) Severe ice on inside of windows after standing for a while usually indicates water in the form of melted ice inside the vehicle. (windshield replacement leaking, melted boot snow on floor boards, bad sunroof/moonroof seals). I wish you well in you chase...P.S...Try breathing out your nose when it is horribly cold outside, it is less of a straight shot to your windows with exhaled aqua.
 
I go along with the leaking windshield/body theory try driving the car with the A/C and the heater on. A good glass shop may be able to find a leak.
 
My car would get frost both inside and outside the main window at winter. Outside frost is solved with a sheath that covers the whole window, the frost will stay on the sheath(there is product to be bought in the store for this). Inside the car is a bit more trouble. I had to scrape the inside too, and when I was done I could make a snowball! A lot of hot air from the fans solves it, but not until the car gets hot, and that might take some time. I have found this in many cars, cant say that there isnt a leakage of some sort anywhere, but if it gets really cold outside there is often frost on the inside to. My guess is that the air in the car are warmer than the one outside, and when the temperature drops rapidly the moist in the hotter air inside the car forms to frost on the windows. After I had removed the inside frost, and had driven a bit, I had to stop to remove some new frost, the new came from my breath. But as soon as I got some heat in the fans, that problem was solved quickly! Maybe there is some sort of sheath you could put inside the car on the windshield?
 
I understand that some frost/fog may be common, but like I said, this is far worse than typical.
It isn't just the windshield, it's every window in the car. Just as much fog/frost on the back and side shields as the front.

Every couple months I need to top the coolant off, I wonder if this might have something to do with it?

Maybe buy a bunch of silica packets and throw them everywhere? :green:
 
Might sound silly but I know it works on a full glass storm door. The other week we were supposed to have some snow. So the ever vigilant snow watcher that I am I opened up the front door so I could view the front yard while I sat in front of a roaring fire and BANG as soon as I had the door opened up the glass fogged completely. Foiling my plans of snow watching, well a few minutes on the net I found a simple and inexpensive answer...shaving cream! Thought it was silly but I did not want to have to run out to the store and buy a product specifically designed to keep fog off windows so I tried it. It worked fantastic. No fog at all! Just put a little bit on cloth and wipe onto glass and then use another to wipe it dry.

Might not fix your problems exactly but I thought it was a neat trick.
 
+1 on rainx.

I find it works best if you apply it and then clean it off with glass cleaner. It still works and you don't get glare.
 
If you have AC, crank it up, otherwise full heat toward windshield. Before you park each night leave the doors open for ten seconds or so to vent out the moisture so they don't condense onto windows by next morning.

Also consider carry a small squeegee and ice scraper next to you. I have both in driver's door pocket, but then again my windshield is perfectly flat and close to me.
 
I'm with Greg on this one. I bet you have a very small leak in or near your heater core. As others have said, if you can run the air conditioner and heat at the same time, it should help. The cold AC evaporator core condenses the water out of the air before it gets to the windows.
 
Get yourself a girlfriend and enjoy the new found privacy of your car :nana:
Pablo

Maybe that's what's already causing the fog! :sssh:

I'm with the others here who suspect a small cooling system leak. For what it's worth, my defroster mode activates the A/C to dry out the air, and it works quickly. But if I open the window even a tiny bit, it fogs up again because I've allowed another batch of moist air to enter. So I think the culprit is the additional moisture being introduced by the leak.
 
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I think you're right about a leak somewhere. Talk about a needle in a haystack though.

I tried driving with the heat/ac on, and it worked no better :(

What about my silica packet idea? Maybe something else a little more practical?

Whatever the cause, there is obviously a whole lot of moisture in the car, and if I can give it a good drying, it might at least help reduce the problem for a while.
 
Is your system stuck on recirculate from using AC this summer?

With my wife's car we had to clean the inside of the glass really well and make sure she didn't accidently turn on the recirculate by accident.
 
I think you're right about a leak somewhere. Talk about a needle in a haystack though.

I tried driving with the heat/ac on, and it worked no better :(

What about my silica packet idea? Maybe something else a little more practical?

Whatever the cause, there is obviously a whole lot of moisture in the car, and if I can give it a good drying, it might at least help reduce the problem for a while.

It's not hard, add flourescent dye to cooling system and go nuts with UV light. For your ac make sure it's functional and not low on freon or anything.

Silica absorbs only pitiful amount of moisture, if it's already fogging it won't do anything.

For what it's worth, my defroster mode activates the A/C to dry out the air, and it works quickly.

I HATE that "feature" on newer cars, the ac button is an inch from defrost button for christ's sake and I'll turn it on if I need it. Sometime I just want hot air to go toward windshield to melt ice/snow, or just not blowing at me directly and really don't need the compressor running and sipping gas.
 
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If you have a house with a driveway or a parking space with access to an electrical outlet this is an economical solution.

http://wup.defa.com/en/wup_applications_cars.html

I think Eberspächer et al. manufacture fuel driven variants of heating systems. But they are very expensive. http://www.eberspaecher.com

The point is that when the car is regularly warmed up moisture doesn't build up and the car stays dry.

Anyway, it's a very nice system. I love it, even though I have to remember to plug it in and set the timer.
Stefan
 
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