Facelift Fogging on inside of windscreen?

Spinstorm

Registered User
Joined
Feb 21, 2017
Messages
2,078
Reaction score
1,233
Points
113
I’ve noticed over the last month that when I leave my car in the evening I get fogging in the inside of the front window if it’s night time. (No where else in the car).

Other cars parked near me aren’t getting this issue - so it’s not down to the weather. I can’t figure out what’s causing it.

Any thoughts?
 
I’ve noticed over the last month that when I leave my car in the evening I get fogging in the inside of the front window if it’s night time. (No where else in the car).

Other cars parked near me aren’t getting this issue - so it’s not down to the weather. I can’t figure out what’s causing it.

Any thoughts?

Interesting, my daughter has a loan car at the moment Audi A5 S-Line and it has the same problem. We have cleaned the window with microfibre cloth which does remove the film but within a few minutes you can actually see the ‘film’ reforming on the screen.
I think like our car it just needs a proper clean with a quality product.


Sent from my iPhone using Tapatalk
 
  • Like
Reactions: Spinstorm
I’ve noticed over the last month that when I leave my car in the evening I get fogging in the inside of the front window if it’s night time. (No where else in the car).

Other cars parked near me aren’t getting this issue - so it’s not down to the weather. I can’t figure out what’s causing it.

Any thoughts?

Very odd! I’d ask Audi to take a look, just park it up there overnight and let them see it.

Or, get some Rain-X Anti Fog?
 
  • Like
Reactions: Spinstorm
My thinking would be that the screen is probably warm because its had the blowers on it. Once it's switched off, the difference in external temp causes the condensation.

Or, check your carpets aren't wet / damp.

I get this in my 8P but I've always put it down to short journeys, wet shoes making the mats wet, not being able to fully dry out etc.
 
  • Like
Reactions: Spinstorm and richinsoton
My thinking would be that the screen is probably warm because its had the blowers on it. Once it's switched off, the difference in external temp causes the condensation.

Or, check your carpets aren't wet / damp.

I get this in my 8P but I've always put it down to short journeys, wet shoes making the mats wet, not being able to fully dry out etc.
It's not because the screen is warmer than the surrounding air, it's because it's colder.

Warm air carries more moisture than cold air, and as the warm air comes into contact with a cold surface - the screen - it loses the ability to hold the moisture, hence the condensation.

For what it's worth, I reckon that it's caused by residual warm air from the heating system rising through the screen vents. Even if they were closed they aren't airtight, and the bulkhead beneath is warm from an engine a few inches away.

If you had a leak of any kind resulting in damp carpets it would affect all the windows and not just the screen.

Been there and done that with flooded plenum chambers on A6s and allroads.



.
 
  • Like
Reactions: KenL, Spinstorm and richinsoton
If you're running the aircon when you switch off there will be a lot of moisture on the chiller plates in the ventilation system, most of which will end up on the windscreen overnight. Using aircon to clear the screen works very quickly but as soon as you turn it off the screen will mist over again unless the car is really warm.
 
  • Like
Reactions: Spinstorm, Dan_G, richinsoton and 1 other person
The reason VAG group cars do this is because of how WELL made they are. They're much better insulated than other brands.

Their are methods to reduce this effect though. Take the matts out the car overnight for one night and let them dry out any moisture. Make sure theirs no wet coats or boots in the vehicle. When driving home turn the aircon/heating off and open the windows a couple of miles away from your house to let the moist air out and allow the cabin air to reach the same temperature as outside.

For me I'll find one day theirs no misting, then it will rain overnight, I'll get in with wet shoes just once for 15 minutes. And it will steam up for the next few nights.

You should always drive the car with your aircon ON, as that works as a dehumidifier and gets rid of moisture in the air.

Hope this helps
 
  • Like
Reactions: Spinstorm
I always have my aircon in low - and on the demist icon.

I think it’s not cold enough for the heating as far as I’m concerned but it’s too warm to not have any air movement.

I also tend to drive with the sunroof open unless it’s raining as again I get good air flow (even though I probably look like a fool in October).

Maybe it’s down to the aircon as you guys suggested above that it is happening. Thanks!


Sent from my iPhone using Tapatalk
 
I have my air-con on automatic all the time. My A3 gets put away in a garage every night even if is raining and the car is wet. I never have any problem with misting up of the screen or for that matter have I on any of the other A3s I've owner. Remember the A3 is a German car is designed to German standards and most Germans put their car in a garage at night. In this country most garages are used as store rooms!
 
I have my air-con on automatic all the time. My A3 gets put away in a garage every night even if is raining and the car is wet. I never have any problem with misting up of the screen or for that matter have I on any of the other A3s I've owner. Remember the A3 is a German car is designed to German standards and most Germans put their car in a garage at night. In this country most garages are used as store rooms!
If you put your car in a garage every night the screen won't get as cold as the screen of a car parked outside. Warmer screen means lower temperature differential, and lower temperature differential means no condensation.

It's physics, init.

.
 
  • Like
Reactions: Jassyo06
Try cleaning the inside of the windows with a high quality glass cleaner, dirty glass can hold on to moisture
 
  • Like
Reactions: Bitzieee
If you put your car in a garage every night the screen won't get as cold as the screen of a car parked outside. Warmer screen means lower temperature differential, and lower temperature differential means no condensation.

It's physics, init.

.

I agree, init


Sent from my iPhone using Tapatalk