Interior Moisture - Windows Fog

[Ludigdrums]

Hey all...I have noticed that the windows in my Vette will fog up, all by themselves, when it has been sitting...no doors open or windows or anything. The center guages will fog up too.

What causes this?! Have any of you ever had this?! Any ideas?!

Thanks!

- Jeremy

 

[78SilvAnniv]

Somewhere in your interior, something is wet.

High humidity?
Leak in your heater core?
T-tops leaking?
Heidi

 

[Fishman]

I agree with Heidi... and sometmes the chemicals from all of your cleaning solvents will also, over time, create a film on the inside windows.

 

[tomtom72]

Hi Jeremy, I agree with everyone else about all the possible places a vette can leak. I have a few questions, retorically speaking. Did the pervasive fogging get noticed suddenly? Or did it become more pervasive with time? Usually with a heater core you first notice a small spot of fog right above the defroster opening at the base of the windshield. That's the tell-tale no one wants to see. With time the fog spot grows as the leak gets worse. This is going to sound stupid, but I had this happen to my vette and I sniffed at the heater air out let on the pass side. I ran the motor and set the HVAC controls to heat/defrost and stuck my head down there and I could smell the coolant in the airflow. I looked stupid doing it. If there are no wet spots in the car from other possible leaks you may give it a try. tom

 

[norvalwilhelm]

I agree with tomtom72. When the heater core springs a leak you notice fogging on the windows right away.

 

[LanceB]

I used to have to store my car outside with a car cover. I bought these moisture packs (they collect moisture) they sell in most catalogs that helped.

 

[jimred75]

Like the rest the heater could be one reason but with my 80 which is also stored outside with a cover, we found out some moisture came thru the cover. After a little research with a hose I found small cracks at windsheld bottom where the wipers sat and when it rained(god forbit it has outside) or washed some of the water got in and resulted in the fog also.

 

[goingballistic]

Check the carpet on the passanger side under the dash, against the fire wall, if it's moist can you say "Heater Core".

This was the first indicator that mine was going and I didn't catch it until it let go completely............now I can say "New Carpet"

Paul.

 

[Blue82]

Being that the gauges are fogging up, my money is ona leaking windshield that is leaving water behind the dashboard. When I lost my heater core, I had all the signs listed above, but I have never had my gauges fog...even if my t-tops leak and I find water in the car.

 

[Ludigdrums]

Thanks for all of your responses...I think you are all right! The fogging is most definately happening from interior moisture.

I have had this problem always, and I do have water in my passengers side floor. I tried to remedy this by caulking around the heater core. I don't have any antifreeze smell and the heater works great. It seems to just be water. The caulking seemed to help, but not completely. I don't get any other leaks from the windshield or T-tops...but I do get water inside my doors, and I have a feeling that it gets inside as well. I think I should also check to see if I have a vapor barrior in my doors...I'm thinking that I don't.

Thanks again everyone!

- Jeremy

 

[goingballistic]

With that said, I just replaced my heater core this spring. The AC housing inside the engine compartment had a gasket on it. When I replaced the core I forgot to replace that gasket. First time it rained I had water inside the floor board on the passenger side...........you can ONLY imagine how ticked I was thinking it was the core again ad .......turned out that the gasket around the AC housing was missing ( my bad) Chauked it and it's fine.....I chauked cause next spring I'm dropping a 383 in and I'll fix that the right way while the motors out this winter.

Cheers.

Thanks for all of your responses...I think you are all right! The fogging is most definately happening from interior moisture.

I have had this problem always, and I do have water in my passengers side floor. I tried to remedy this by caulking around the heater core. I don't have any antifreeze smell and the heater works great. It seems to just be water. The caulking seemed to help, but not completely. I don't get any other leaks from the windshield or T-tops...but I do get water inside my doors, and I have a feeling that it gets inside as well. I think I should also check to see if I have a vapor barrior in my doors...I'm thinking that I don't.

Thanks again everyone!

- Jeremy

 

[Dave Z]

Here's a long shot, but it cleared the probelm I had with water on the passenger side floorboard...check the weep holes and make sure they are not blocked. My passenger side in particular was gunked up so bad, that water could not find it's way out of the bottom! Just another thing to check that may help.

 

[Ludigdrums]

The weep holes in the door? If so, I only seem to have one rather large hole (~1") at the end of the door (door lock side). Where should they be?!

Thanks again!

- Jeremy

 

[George Black]

Jeremy: I do not think that Dave is refering to weep holes in the door. He is refering to the "weep hole" behind the right side (passenger) kick panel. When water/rain enters via the cowl area below windshield, it drains out the bottom of the fender area via a "weep hole". If hole is clogged the water can not exit/drain; instead it drains into the passenger floor area by the kick pad.

Bod Chadwick's home page has a good method re locating the hole: Insert a light behind the passenger kickpad, look upward from under the car, and light should be shining downward through the "weep hole".

Dave, if I am mistaken re your weep hole comment let me know!--G.P.Black

 

[Dave Z]

George, you are correct and thank you for clearing up my mess:crazy. Apologies Jeremy, I should have been more exact about the location of the weep holes behind the kick panels. I hope this helps...good luck!

 

[Ludigdrums]

Thanks again guys for the replies!

Well, we've been having a lot of rain this week in LI, and I decided to take a look to see if I could see where the water is coming from. The weird thing is, it doesn't appear to be coming from anywhere. There is nothing else that is wet except for the floors. My guess is that it is from the doors and the sill plates aren't doing their job. But, again, weird thing is, the carpet isn't wet anywhere where but on the floor bottom.

Strange!

- Jeremy

 

[firedawg]

Heater Core:
I had this problem in my '93, windows fogging up all the time, and the defrost took forever to clear it up, but the heater worked fine. The way I diagnosed it was to clean my wet-vac out really good and vaccuum up the liquid then look in the canister to see what it looked like, sure enough it was coolant

Weep holes:
Now I just got my '78 and noticed a wet driver's side floor just after getting it, at first I just wrote it off as leaking weather stripping but I didn't see any streaks down the windows or on the doors or any other carpet for that matter, just like you described, with these weep holes, is there on one on the drivers side? Where is this drain that can get clogged up? How do you unclog it?

 

[JohnZ]

There's a drain hole for the side plenum (both sides) just behind the #1 body mount, visible from under the car; it gets clogged up with leaves, etc., and rain and wash water rises in the cavity instead of draining and leaks into the car at the bottom of the kickpad, using the carpet as a "wick".