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Fogging Windows 2

I posted a question a while ago (see fogging windows) and this morning was able to find an absolutely sopping wet section of carpeting in the backseat of my car. So my question now, is what next? I found the wet spot, how do I fix it?

[b][i]Was This It?

Fogging windows
I have a 2001 Chevy Malibu LS that I bought in 2004. Last winter it developed a fogging issue. When the temperature drops the inside of the windows fog up, starting in the back and moving forward. I have to run the defrost on full to get it to make a dent on the windshield and even then it leaves a heart shape that’s cleared. It has no apparent trigger either. The other day I had the car out and warmed up for about 15 minutes and it started fogging up. Last winter it was typically worst on the day after a snow storm.
I’ve been to three garages about it. One said there was a hole in the floorboards, one said it was a problem with the air conditioning and the third just really didn’t know. This becomes something of a safety issue when it gets really cold because the fog built up on the windows will freeze over so I have to roll down the windows to see. Please help!
Posted by: trinitylab[/i][/b]

Keep in mind that the water is possibly coming from a remote location (not necessarily the back seat area) and traveling underneath the carpeting, via gravity, to the lowest point. These leaks often require two people working to locate them. One inside the car or trunk and one outside with a hose.

Is there any evidence that this car has had collision damage repaired? You might want to have a body shop give it a quick look.

Leaks that appear as wet carpet in the rear are likely to come from:

  1. plugged drains in a door, causing the water that gets in at the base of the window to build up in the door and pour in from the bottom edge of the door inner panel.
  2. Bad door seal
  3. Sunroof drain hose that has pulled out of its exit hole and is discharging water into a body cavity.
  4. Leaking rear window seal or any leak into the trunk if the body pan is shaped such that it can drain into the back seat. Tail lights are a common leak point, but leaks from there usually find a low point before finding their way to the passenger compartment.

I’m inclined to cross two items off the list you gave me because the car doesn’t have a sunroof, but also when I was checking the car yesterday, there was no water in the trunk - even in the spare tire well.
So I guess that leaves the plugged door drains or the bad door seal. How would I go about fixing those? Are they something I could do myself, or better off having a body shop do them? Thanks for your help!

Well, if it’s an issue that I have to figure out with a hose, it won’t be happening for at least six months till the temperature finally gets above freezing again.

The only collision I’m aware of happened before I bought it and that was replacing the front bumper.

Thank you!

two issues come to mind.

where do you live? do you use AC all the time? if you don’t use AC then condensation isn’t an issue.

i would be inclined to think it is a rear door seal problem. usually leaks dont migrate from front to rear, or trunk to rear seat.

look under the door. there are usually two or three slots on the bottom of the door. these are to let rain out. but if they are full of crud, or have been plugged with body filler (poor quality repair) then they may not be draining properly. find the slots and slide a ruler up into them and along them to see if they are clear.

take a garden hose and run it on the roof. sit in the back seat and look for leaks. shut off the hose and open the door. look for leaks along the sides of the door posts. open the trunk lid. is the gutter area clear of debris? all the way around? inspect the rubber gaskets. on the doors, and trunk. any broken or deformed seals?

At The Body Shop Where I Worked To Check Doors For Proper Fit And Sealing, We Would Use A Dollar Bill!

I never tried it on a trunk, but I suppose you could. This would work best with a dry car. Standing outside the vehicle, close half of the bill (you will no doubt need to use a longer strip of paper) in the sealing part of the door (without closing your fingers in it!) Try to carefully pull it out. It should offer some resistance or drag if the seal is contacting well. Go around the door, wherever possible, sampling several places, trying to find any places on any doors where the seal is not contacting. You may be able to this from inside, also. You will quickly develop a feel for proper contact. You may not find a problem, but this may eliminate one area of concern.

The wet spot might not be the problem. On your air circulation control are you recirculating the air inside the car or bringing in fresh air from the outside.
Recirculating the same air within the car can also cause fogging