Florida Mike

Does anyone else have a problem with a small patch on their front windshield fogging on the outside?

I am in Florida so the high humidty doesn't help but unless its bright and sunny, I get a patch right in the center of the windshield that fogs up even if its not raining. A pass of the wipers takes it away but it comes right back.

Been playing around with the climate control settings but nothing seems to work. I do keep it very cool on the interior so thats probably not helping.

Any suggestions? Rain X anti-fog or is there a configuration of the climate controls I am missing?

Mike

Ron C!

I run my A/C at 65 degrees, never experienced any issues like that.

jbondfl

Sounds to me like the defroster vent isn't closing tightly. That casues the windshield to get a continuous blast of cold air resulting in your fogging problem.
I get that in my Yukon on the side window occasionally. I just look at it and smile knowing how cold the AC must be to make that happen.

bhoch

I have not seen this on my '00 coupe. Is your car running higher temps then usual?

karl31

Have the same problem on my 98 vert, happens only on startup and goes away in a few minutes.

jrose7004

I haven't had that problem.

MygreenC5

On my 00' my blend doors wern't working because of a vacuum leak under the battery and I had that problem because air was coming out everywhere. Check to see if air is coming out top & bottom.

R Devil

Mine does the same thing on humid days here in Iowa. Haven't found the cause or a solution yet.

Florida Mike

Might have to check the doors and such you guys mentioned.

I do keep the car very cold inside. Its on 60 degrees and always recirc the air. Engine temp seems normal. It is raining here ALOT lately and relative humidity stays around 85-100%. (Yes, its THAT humid!) The only thing I can figure is I have it so cold inside and that area is where some hot air from under the hood might escape via the cowl? I thought it was better sealed than that but maybe not?

I'll check the HVAC air flow and maybe just a good coating of RainX anti fog will help?

Mike

TEXHAWK0

If the fog is on the outside, you are just getting the windshield so cold in that area that you are condensing moisture from the air outside.
Most likely, the only way to get rid of it is to raise the temperature setting inside the car.

Florida Mike

Tex,

Yeah, thats what I thought. I am just wondering why it is getting cold in that specifc area? Must be an A\C air leak up through the dash vent even when I am running the air flow out the fronts?

paullywalnuts

Mine does it (Fl also) had the dealer "fix" it but they didn't "fix" it..something to do with vacuum line..It only bothers me in the summer.

1sickz51vette

I live in florida and i have the same problem, it really annoys me to have to hit the wipers especially after a good detail! The problem is the actuator located under the dash near the defroster vent. Most likely its blowing air out all the vents and thats the culprit, I remember reading a good write up about it. If someone could post the thread it would be awesome!

RedSoxFan

I had the same problem, and it was a vacuum leak. Do a search and you'll find plenty of DIY info. I decided I didn't want to tackle the repair and had the dealer do it, they traced the leak to the hose beneath the battery where it passes through the firewall. The dealer charged me $200 and to date it's the best money I've spent. The A/C settings all work correctly now, and blows cold air like crazy.

TracyRR

i am having the same issue.... i noticed that it goes away when i set the "mode" to just the dash vents and not dash and floor vents.... it fogged on me this morning until i changed the mode.... worked for me. Good luck.

TEXHAWK0

I would not be surprised if GM did not design the dash vent to always have some air flow to the windshield to prevent fogging on the inside. (Just like they make the AC run even during the winter to lower the humidity of the air) This only creates the problem when there is high humidity outside and you lower the inside temperature below the dew point.

Vetteman Jack

Never had it happen on any of my Vettes, but on our work cars it has happened. Haven't found the solution yet.

Mad Dog Peter

Florida issue. Only happens during very high humidity days. Probably not a perfect seal there, but I have the same issue and just ignore it. Our humidity is SOOOOOOO high. When I run my A/C my trunk lid sweats like a bottle of beer!