Windsjield fogging??

[TBK1]

when it rains my front windshield tends to fog real bag and using the defroster in hot or cool doesnt seem to do any good, it's blowing right but still fog, got to wipe it to see and then it refoggs with streaks, tried cleaning and all but still same when it rains, any body else or someone found a fix!!

[TomoHawk]

Is there any other moisture in the car when it's raining? Any leaks you 're not aware of? Having any standing water (like having wet carpets or something) saturates the air with water vapor, and the defogger won't work well.

[sblake01]

My car had that symptom when my heater tee had a small leak. At first, I only would notice the fogging when the wheather was cold or rainy then it became more noticable as the leak got worse. I hope that's not the case for you because that wasn't a real enjoyable repair.

[MikeW]

On modern cars running the defroster - even in the winter time with the heat on full - actually turns on the air conditioning compressor. This has the effect of dehumidifying the air before it comes out the vents. This drier air is much more effective at removing fog from the inside of the windshield. Warmer air should work better than cooler air because when the air expands it can absorb more moisture. This is how a hair dryer works. Unfortunately for those of us in warm humid environments there's not a whole lot you can do. With it raining hard there's 100% humidity and you've got your windows rolled up to keep the rain out so just breathing in the car tends to fog things up even more. If you don't have A/C there's not much more you can do. There are commercial products (like Rain-X but for the inside) that supposedly help with fogging. I've never tried one of those so I can't comment on how well they work or if your glass gets addicted. When Rain-X starts to wear off things are actually worse than not having any at all so once you start using it you have to keep using it.

[EScanlon]

Rain-X for the inside is guaranteed FOG for life. Bluntly---DO NOT USE RAIN-X FOR INTERIOR--- Black Bottle/Packaging.

It is a bad product, I used it on my Acura, and only when the windshield was cracked and was replaced was I able to get rid of it.

You'll have streaks AND fog on sunny days (it's impossible to polish it to fully clear), it doesn't really work to prevent fog on the inside, and it resists Lacquer Thinner, Acetone, M.E.K., Naptha and Mineral Spirits. It will simply NOT clean off --- EVER. You will, in essence, RUIN your windshield.

You might do another check though. Check the hoses to your defrost nozzles from the heater plenum. If those have cracks in the bellows portion of the tubing, you're loosing the bulk of your defrost capability right there. Additionally, are you sure your heater core DOES heat and isn't plugged?

FWIW

E

[beandip]

Another thing is to check as best as you can for a coolant leak . You might have a heater core or water valve beginning to leak . It doesn't take much to cause the problem you are seeing . Gary

[MikeW]

Rain-X for the inside is guaranteed FOG for life. Bluntly---DO NOT USE RAIN-X FOR INTERIOR--- Black Bottle/Packaging.

Are you referring to the Rain-X anti-fog product? I certainly didn't mean to imply that regular Rain-X could or should be used on the inside. Like I said I've never used one of the anti-fog products.

[DeesZ]

Ditto on the coolant leak, Beandip. That was my first thought. Depending on what is being used as coolant, you may/may not be able to smell it distinctly. When a leak is bad enough, your defroster can actually create more 'fog' than it gets rid of. Also, some coolants will actually leave a thin film of crud on the inside of the windshield that you may be able to see if you get it in the bright light at the proper angle. That's been my experience, anyway. Please let us know what you find as the root cause..... mine does it every now and again...

[Sailor Bob]

I had a similar problem - slide set to defrost, lots of blower noise and lots of moisture on the windshield. Slide was not functioning properly - inner wire core was folding at the sheath end and never permitting the defroster to engage.

The repair required a new cable, but impatience and thriftiness (cheap) kicked in and I cut a peice of damaged antennae off, formed a sleeve for the end of the cable to prevent the folding - cleared the windshield in a minute.

Probably useless information, but might help.

Good luck

[TomoHawk]

There's an idea-

Make sure the cables are working correctly. If the fresh air door won't close when the defogger is on, you'll be blowing water vapor onto the windsreen.

[EScanlon]

Are you referring to the Rain-X anti-fog product? I certainly didn't mean to imply that regular Rain-X could or should be used on the inside. Like I said I've never used one of the anti-fog products.

The EXTERIOR use Rain-X, the stuff that comes in a Yellow Bottle with a Black Cap is EXCELLENT stuff. I highly recommend it on the windshields as well as the side and rear windows. I also applied it to my Headlight Cover Lenses.

No, I wasn't refering to the Exterior Rain-X.

The INTERIOR Rain X comes in a Black Bottle with a Black Cap. Sometimes (IIRC) it also says "Anti-Fog". If it says it's for use on the INSIDE of your Windshield, then that is the stuff NOT TO USE. DO NOT USE THE INTERIOR RAIN-X.

I'm not the only one that has had this problem. There is no possible way of polishing the interior of the glass to the degree that this stuff requires. Additionally, it never really "sets" enough that it is hard enough to buff. As a result it's always catching dirt and worse of all is always a glare hazard from both the sun and other cars. So you're constantly cleaning your window and re-applying it and doing it all over again in a short while. The end result is that you cannot buff it clear and smudge free, and it's impervious to every cleaner I tried, even lacquer thinner and M.E.K. and it would NOT remove.

Use it as your own risk, but this is a fore-warning.

I kid you not. After battling it for two years, my windshield cracked. That's how I got rid of it.

E

[sleepyzzz]

i wonder if goof off would remove it. a friend used that to remove old tinting residue on a vehicle he purchased,and it worked great on that.