Super Foggy Window Problems - The Unofficial BMW M5 Messageboard (m5board.com)

xr4tic · 21st January 2008, 20:50

Hey guys, I'm hoping someone can help me with this problem.

Every single window in my car fogs over badly, and I don't know why.

If I turn the defrost on, the best it can do is clear off the front window, and half of the front side windows. 10-15mins later, the side windows are fogged again, and the windshield is starting to fog again.

I turned the recirc off, that helped a little bit. If I turn the A/C button off, it gets much worse, so it's working. Maybe not 100% though?

The other day, I got out of work, went to my car, and I had to scrape off the frost on the INSIDE of the windshield

It's almost embarrising, I'm driving an M5, and the guy next to me in a $50 beater Chevette is enjoying Fog-free windows, along with every other car on the road.

Engines, suspensions, electronics, no problem, when it comes to HVAC problems, I'm clueless. I'd guess the A/C system isn't removing all the moisture, but no idea how to troubleshoot it.

iconoclast · 21st January 2008, 20:53

first things first i would clean the windshield properly and thoroughly... typically i use alcohol and a newspaper, however 3m glass cleaner is second best imo... i would see if the problem appears again... since its in all your cars i would start there, but the common denominator in that scenario is you... maybe you sit too close and breathe heavily lol???

Diny · 21st January 2008, 20:57

Stop boning in the car!

I agree with what iconoclast said. Try turning the AC on, too. It doesnt have to be cold, but the AC will remove most (if not all) of the humidity. Worked like a charm in all cars I try it on. The heater could be blasting, but as soon as you turn the AC on, fog goes away.

xr4tic · 21st January 2008, 21:05

I see, so you drink alcohol, and clean the windows with newspaper? j/k

I forgot to mention I already tried cleaning the windows, I forget the brand, but it was made for cars.

I always keep the A/C on. I used to keep the Recirc on too, but it just makes the problem worse.

It doesn't happen in all my cars, just my M5, I have no problems in my wife's GTI. I'm 6'6" so I'm not sitting too closely.

The problem does get worse if my wife is in the car.

Diny · 21st January 2008, 21:16

Quote:

Originally Posted by xr4tic

The problem does get worse if my wife is in the car.

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Quote:

Originally Posted by Diny

Stop boning in the car!

Nabio · 21st January 2008, 21:22

I used to have this problem whenever winter rolled around in my Subaru that I drove to high school. I learned a few things from it. First, I would use newspaper and 3M glass cleaner or windex or something to clean the windows. That gives you a good place to start.

The problem is that the air inside your car has a lot of moisture. Moisture loves to sit on the windows, condensate and then freeze. This happens really easy when the inside of your car has humidity and warmth whereas the outside is dry and cold winter.

I finally stopped this problem from occurring by opening up the windows (all of them) or sunroof or something for about a minute or two before parking for the night. The key is to let out all of the wet air inside the car and to balance it with the dry outside air. It may also be fixed as easily as driving home with the sunroof cracked open. Just think about getting the wet moist air out and you'll solve your problem. I found that the moisture seemed to build up over time, and if I didn't do this for a couple days the problem would get really bad. Experiment, and hopefully you can get that dangerous situation of all frozen fogged windows remedied.

xr4tic · 21st January 2008, 21:37

That sounds like a temp solution, I'd like to think the HVAC system in the M5 can handle a little moisture.

I've tried driving with the sunroof open, windows cracked (sometimes in the morning the windows are frozen shut)

jclyman · 21st January 2008, 22:43

I've had the problem from time to time.

First, turn OFF the recirculating air. It just makes it much worse. (I always drive with the Auto Recirculating Air on, except when I need clean windows.)

Second, make sure A/C is ON ... it can be set high (temp), but it should be ON as it removes almost ALL moisture.

Third, I would turn ON the front window defroster ... and, leave it on as long as necessary (it may automatically shut off after a few minutes). It's the button with the NON-rectangular window with arrows on it. (Rear defroster won't do much to reduce moisture ... the rectangular window with the arrows.)

Fourth, if you still need help, crack the sunroof ... The rear opens if you push the sunroof button.

(I was specific, as I wasn't sure how long you have had your car. Most here have never had a problem.)

gsfent · 22nd January 2008, 00:39

Quote:

Originally Posted by xr4tic

That sounds like a temp solution, I'd like to think the HVAC system in the M5 can handle a little moisture.

I've tried driving with the sunroof open, windows cracked (sometimes in the morning the windows are frozen shut)

If there is excessive moisture in the car, you might want to find out why. Bad window seal? You may also have a leak in the heater core, although typically you can smell that inside the car. The AC should be powerful enough to remove the moisture.

As a temporary aid, why not leave some Damprid open over night to absorb the moisture? After a few days, you should have a reasonably drier vehicle.

Most grocery stores sell it, usually in the soap and glass cleaner aisle.
Regards,
Jerry

JBss · 22nd January 2008, 01:31

vent the sunroof and use the AC button

DouglasABaker · 23rd January 2008, 04:30

Based on the responses I can only deduce that I am the only person who just pushes the "Defrost" button when my windows fog up... This in turn: turns off recirc, turns on A/C, and blows the hottest air possible.

If you'd like to maximize your defrosting, you should... turn off the recirc, turn on the A/C, and set the temperature all the way up. Oh, and obviously make sure it is blowing through the top vents at max blower.

If that doesn't clear your windshield then you likely have a problem with your recirc and it is not disengaging. Try manually turning it on and off with the fan on high. You should be able to hear it engaging and disengaging.

Another possibility is that your A/C is low on gas and is not able to adequately cool (perhaps it has frozen - it is cold in MI)...

d-