Hey guys,
Today its been raining heavily off and on. When its not raining, the sun was out.
When I left my office I came out to find all of my windows with a heavy fog built up on the inside of the windows.
This isn't the first time that this has happened.
It took about 5 mins or so to clear the fog so I could drive.

Logic would dictate that there is moisture inside the car somewhere.
Well, I couldnt find any moisture nor any source.
I checked all the floorboards, no luck. I checked sunroof track and it was was bone dry as well.


Any suggestions?

Thanks

 

Humidity can fog the windows and with the rain could be just that, I would check again for damp carpets etc also did you run the ac to help clear.

 

Yes I did run the a/c, thats how I was able to clear it.

 

I have had high humidity situations where it took a while to clear windows if you have no water getting in its probably nothing to worry about.

 

I have had the same humidity issues...no internal leaks...just ran the AC..and cleared up

 

stop having s@x in the car...LOL

 

My lower windshield has serious condensation, its annoying that I have to adjust the blower to legs only...

 

Check the water drains under the front trunk lid and the plastic panels on each side of the battery. If these are blocked water collects in the basins and the cabin air can be extra humid which makes the job to clear the fog harder.

If you find the drains blocked also check for moisture in the cabin. The carpets and feel under the seats and along the bottoms of the doors.

Also, be sure the insides of the windows are clean. Over time they collect a film of dust and the outgassing of the interior materials that exacerbates the tendency of the windows to fog.

You might have to have the evaporator and its water pan/drain looked at too. Sometimes the pan drain plugs up and the drain remains full of water which makes for more humid cabin air.

 

Ditto to checking those areas. A few years back my Audi S4 had a national recall for similar problems but with the drain for the sunroof drain that would get dirt and clog the tube causing water to leak into the rear passenger floor pan causing condensation.
Makes me want to go check mine out

 

Thanks for the tips.
I have checked the drains by the battery and they seemed clear.
All the carpets were bone dry. (yes I checked under the floor mats)
I do religiously clean the film off the inside of the windshield as I've been keen to outgassing for many years.

As for the a/c drain pan, I do see it draining on the driveway everyday.
On really humid days when I ride with the a/c on and the windows down for a while I have noticed my right leg getting some moisture on it when cornering hard.
I attributed this to condensation building up on the exterior of the evaporator due to the humidity.

 

I live in Vancouver Canada and we get stupid amounts of rain. One year we had a 100 days straight of rain!! That's in a row.
I've never had condensation issues. And I also never run the a/c. I daily drive my car.
My fx35 though I have to run the a/c if its raining, if not the windows fog up while driving.

 

I had the same problem. It was the recirculation servo that was stuck in recirculation position.