Fogs up like crazy - any tips? E86 Coupe

[kartman]

Hi there fellow Z4 owners

Got a bit of an annoying thing going on with my Coupe. Windows (namely top of windscreen and sides) fog up and freeze up in cold weather.

The conditions in which it happens are usually when weather falls below 0C. My car is garaged and moment I leave it into cold weather, all seems OK as car is warm. I let it park and after a while the moisture turns to fog. Starting up the car it takes a while to get rid of some on the windscreen, but sides remain a mess.

Worse still, I took a road trip at -20C (kind of emergency) and my travel mate and I had to use a credit card now and then to scrape off sides of the windows to keep the frost off. Forget about the rear quarter windows, and defroster was on all the time. I managed to keep the windscreen ice free in important parts by angling all the fan power to the windshield. Needless to say, not nice to drive and also gets quite hot (the opposite of what you want in driving in cold, i.e. you want cold head and warm feet).

So, what are my options? New cabin filter? Replace all the seals? Add some special coating on glass inside? Anything else? Or the Coupe has some pretty bad factory insulation and heating vents are bad at keeping cabin warm?

Appreciate your thoughts on this guys! I drive little, but when I drive on long journeys sometimes it is almost a safety issue.

 

[simonlpearce]

Are you running with the AC on?

 

[mad4slalom]

is your garage not too well insulated , or the car sits for weeks unused, we have two sorned vehicles and they dont like being stood, they both fog up after standing idle. someone here suggested a large bag of scented cat litter open in the footwell may help, so was going to try that. if you are icing up inside though you may have other issues, in the past i had a car with slight leak into the footwell from the heater matrix which caused fogging and musty dampness.

 

[Fastatv]

I would have to think that you have an excess of moisture/water in the car and this would be caused by either a leak somewhere or possibly a faulty heater core, but not likely the heater core as you would be smelling the coolant/antifreeze. I would recommend spending some time feeling in different areas and try to find "wetness'. Check floor pans ( carpet ) front to back, and trunk area as well. You might even sit in the car and have someone spray water around the windows and doors and see if there is a visible leak. Good luck and keep us posted on what you find. :cheers:

 

[Bing]

Are you running with the AC on?

This is a good point... Remember it's not really just air con for chilling the cabin, it's climate control. If you switch the AC bit of it off - the snowflake button ? - the air blowing in will not be dry. Moist air on very cold windows will fog and freeze. I think warm water also freezes faster than cold. I leave the AC / climate control on all the time.

 

[simonlpearce]

Are you running with the AC on?

This is a good point... Remember it's not really just air con for chilling the cabin, it's climate control. If you switch the AC bit of it off - the snowflake button ? - the air blowing in will not be dry. Moist air on very cold windows will fog and freeze. I think warm water also freezes faster than cold. I leave the AC / climate control on all the time.

 

[kartman]

guys, the car does have bit of a damp smell in morning inside. but i run it woth ac always as to other question.

i will investigate the footwells for moisture. something is not right...

 

[Smartbear]

Are you running the blower on the recirculate setting? This will cause steaming issues. Set it to draw in external air.
I don't think the a/c works below a certain temperature & certainly not at -20c
Regards

 

[kartman]

Are you running the blower on the recirculate setting? This will cause steaming issues. Set it to draw in external air.
I don't think the a/c works below a certain temperature & certainly not at -20c
Regards

well... lets say that two of my E90s i ran before this car performed flawlessly in any weather and never fogged up. -30 c was not an issue and i ran the AC auto climate control. cabin was perfect. this thing is ... a mess in comparison!

im suspecting thats this is just an older generation car...

 

[Stratts]

Also consider the cabin filter, if hasn't been changed and is all blocked the airflow is severely reduced and the air quality is hampered. This can have an impact on demisting as well.

 

[bluestreak56]

I would have thought seals myself..

 

[kartman]

I would have thought seals myself..

yeah was on my list and... im guessing $$$!

 

[Bing]

Are you running the blower on the recirculate setting? This will cause steaming issues. Set it to draw in external air.
I don't think the a/c works below a certain temperature & certainly not at -20c
Regards

well... lets say that two of my E90s i ran before this car performed flawlessly in any weather and never fogged up. -30 c was not an issue and i ran the AC auto climate control. cabin was perfect. this thing is ... a mess in comparison!

im suspecting thats this is just an older generation car...

Smartbear means the recirculation rather than just the auto climate control setting. Apologies in advance if I am teaching you to suck eggs, but you can have :

Auto climate control, no recirculation - fresh air
Auto with recirculation - cabin air, no fresh air
Auto with auto recirculation - fresh air unless it detects pollutants in the air (I use this one)

The recirculation button is the bottom right button on the centre controls in this pic, auto recirculation is the circle with the A in it. No lights on it is fresh air.

 

[T2FFN]

I'd put money on excess water stuck in the cabin. When I had the passenger seat out this last summer I lifted the carpet and found the foam insulation/underlay was sodden. This could not be felt from the carpet side 1 tiny bit. The carpet felt bone dry, but underneath it could be rung out. I did my best drying it out but will probably do it again this coming summer. I leave a car moisture absorber under the seats too, (sealed so no mess) which helps a little in keeping the little extra moisture from causing it to steam up. I don't appear to have a leak so no idea how the carpet got wet, or how long it was wet. Could've been before I bought the car even.

 

[kartman]

Are you running the blower on the recirculate setting? This will cause steaming issues. Set it to draw in external air.
I don't think the a/c works below a certain temperature & certainly not at -20c
Regards

well... lets say that two of my E90s i ran before this car performed flawlessly in any weather and never fogged up. -30 c was not an issue and i ran the AC auto climate control. cabin was perfect. this thing is ... a mess in comparison!

im suspecting thats this is just an older generation car...

Smartbear means the recirculation rather than just the auto climate control setting. Apologies in advance if I am teaching you to suck eggs, but you can have :

Auto climate control, no recirculation - fresh air
Auto with recirculation - cabin air, no fresh air
Auto with auto recirculation - fresh air unless it detects pollutants in the air (I use this one)

The recirculation button is the bottom right button on the centre controls in this pic, auto recirculation is the circle with the A in it. No lights on it is fresh air.

Yeah mate, no worries. I use Auto with auto recirculation all the time. The one without recirculation but internal air is mainly for places like tunnels in western europe for example, when you start using your filter pretty agressively (and wear it out). In summer I dont use AC often (easy to get sick I suppose, plus dries the air out, and it is not too hot here). I kinda figured all my habits for auto climate back on my E90s, but E86 is an older generation of a car and I think some things just dont work well. The fogging up issue to me is a complete mystery becuase for 6 years+ I was used to no issues in cabin with climate whatsoever.

I'd put money on excess water stuck in the cabin. When I had the passenger seat out this last summer I lifted the carpet and found the foam insulation/underlay was sodden. This could not be felt from the carpet side 1 tiny bit. The carpet felt bone dry, but underneath it could be rung out. I did my best drying it out but will probably do it again this coming summer. I leave a car moisture absorber under the seats too, (sealed so no mess) which helps a little in keeping the little extra moisture from causing it to steam up. I don't appear to have a leak so no idea how the carpet got wet, or how long it was wet. Could've been before I bought the car even.

Well, first I dont have the cabrio, but the coupe. I wonder where the heck moisture came from. I park almost always inside. LIterally 2-3 hours a day the car spends outside in the elements, as my garage at work is ... a garage and at home i have garage too. This car couldn't be more city car if it tried. So if moisture made its way in, I gotta take it to someone to get this sorted and looked into. I know the cabrios could have that issue with drain holes being full and whatnot, but in a coupe?... hmm... Ill check the vents and all, who knows.

by the way, what sort of moisture absorbent stuff are we talking about? Kitty litter - i only have the eco one made out of wood shavings (we have a cat actually). Would that do? Or I should just put a few bowls of rice in the car over night?

 

[bluestreak56]

Window seals, windscreen seals, door seals, boot seal, rear lights and heater matrix are all places where we got leaks on my old mk2 Scirocco.

Then the water would build up in the driver and passenger footwells as it was the lowest part of the car, causing the moisture being described. This seams very odd for a coupe but I suppose it all depends on the seals and where its been parked throughout its life.

 

[aquazi]

There are a few reports of damp passenger footwells - quite common in most BMW's - the door membrane/ glue fails... and allows water to drip in from the window out at the bottom of the door. .... i would remove your mats and check the carpet isnt wet.

I would bet there is some dampness somewhere.. which is causing the condensation.

as its garage you could prob get hold of an electric dehumidifier and leave it running in the car for a couple of hours.

 

[kartman]

There are a few reports of damp passenger footwells - quite common in most BMW's - the door membrane/ glue fails... and allows water to drip in from the window out at the bottom of the door. .... i would remove your mats and check the carpet isnt wet.

I would bet there is some dampness somewhere.. which is causing the condensation.

as its garage you could prob get hold of an electric dehumidifier and leave it running in the car for a couple of hours.

very familiar with this on the X3 (first gen). And since Z4, X3 and E46 share a lot, I guess it makes sense this carried over.
I know remembered I had a water bottle leak in my car into a seat and probably further on. So I will check that tonight. Meanwhile a bowl of rice has been carefully placed in the footwell while car is parked for now.


However, the fogging up is one thing, what I dont like is the frost on windows in minus 20 weather, I think this is what bothers me. As if heater isnt working properly. Gonna book a trip to mechanic next week, as was planning to change gearbox oil anyway.

 

[dmo]

A ahought - did you wash it and not take out out for a long drive, but instead park it up and leave it for a while? I did that recently, and had a lot of water (moisture) inside on the passenger side window. I remember giving it a really good, long, thorough wash, then parking it on the drive for about 2 weeks before using it again this weekend. Pretty certain it was because of standing water in and around the cars exposed internals which, after 14 days of cold (and quite unusually warm!) weather, it leaked its way into the inside of the windscreeen. 30 min drive and the screen heater on full whack took care of the problem. Won't be doing that again.

 

[kartman]

a bowl of rice seemed to have taken care of all the smell. gone for few days now... will keep monitoring, but seemed the simplest thing did the trick!
@dmo - nope, havent done that!