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Cannot Clean Inside Windshield - Help!

I can’t believe this is happening to me. It’s so silly and yet it has become a real safety issue!

I’ve got what looks and feels like water vapor on the inside of my SUV windshield. It creates
an awful whitish smear that reflects the sun. When the sun is low in the sky I can barely see
through the windshield.

I’ve tried a microfiber cloth with distilled water, isopropyl alcohol, and washer fluid. Nothing
seems to completely clean the inside of my windshield.

It must be water vapor (or something similar) because there is no odor and it is not slick or
greasy. Opening the windows or running the defroster helps a little, but not much.

I’ve been extremely lucky with this SUV. It was purchased new and there has never been a
serious problem. I just had a basic maintenence check at the Ford dealer. They changed
the oil and was handed that sheet showing everything they checked. No problems.

There are a hundreds of glass cleaning chemicals and products. Many years ago I tried Rain-X
when it was a new product. It did repel water, but it was a pain in the neck to use. Do you think
Rain-X might prevent vapor buildup on the inside of my windshield?

Please guys, tell me how to resolve this crazy problem. I don’t want to crash when the sun
reflects off that whitish smear.

I had a similar problem and it turned out the paper material I was using was leaving a smear for some reason. I switched to an old cotton towel run through the washing machine, along with the Consumer Reports recommended window cleaning ratio of water/ammonia/alcohol, and that did the job. I think the CR website has the ratio, I don’t recall what it is. I did have to repeat the cleaning process three or four times to remove all the smear from whatever was on the paper though, didn’t come of the first attempt even with the cotton towel. I expect you already know that a leak in the heater core can cause coolant to condense on the inside of the windows, but you say it isn’t greasy feeling, so I doubt that’s the problem. More likely the source is just the plastics inside the car are outgassing. Most cars have this same problem these days.

If it’s just water, the defroster should evaporate it.

Why did it start now? Has the humidity gone to 100%?

I fear the core is leaking, coolant is getting into the ventilation.

If you want to wipe it clean, use something lint-free: coffee filters are a good choice.

26 ounces water, 4 isopropanol, 2 ammonia, a few drops of dish soap.

I didn’t use the dish soap, sometimes that will leave a little smear on windows.

I use rain-x all the time outside surfaces but I don’t think I would use it inside. My recommendation would be windex or equivalent. The other alternative is full strength white vinegar. I find paper towels to be better than microfiber on glass.
After you get it thoroughly clean there are anti fog products, including rain-x, on the market. I have never used them so can not say if they work.
Really curious as to the source of the coating. Possible outgassing from the plastic components or air conditioner drain is blocked, but that usually will result in water dripping on your feet.

Make sure your defroster is set to bring in outside air and not recirculate. Recirculate keeps the water vapor in the car. Also make sure non of the rugs in the car are wet which would indicate either a leak or a clogged evaporator drain hose.

I learned that when you use paper towels in combination with certain window cleaners, it can remove
the binder from the paper and deposit it on the windshield. Very hard to remove.
The old formula is newspapers and vinegar. Try it.
Try using a cotton terry towel on the inside of the window, in combo with some other window cleaners,
if that doesn’t work.
I have found microfiber is good for dusting, not much else.

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Simple- ammonia based window cleaner and crumpled up newspaper.

This is the time of year for it. The solar glare is really bad and the outgassing etc that coats the inside is really bad. I use the above and it really has no equal in effectiveness IMO. The only trouble I have is finding newsprint anymore… :wink:

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Wad up a piece of dry newspaper and try that. That worked for me in the past. A dry microfiber cloth should also work, and you already have that. This assumes that it is outgassing from the dashboard.

If it comes in through the defogger ports, it could be antifreeze, usually ethylene glycol or propylene glycol. They both dissolve in water, though. This makes me think it might be an oil of some sort. If that is true, then a solvent like isopropyl alcohol (IPA) will work if it is a non-polar oil. If it is a polar oil, acetone should work. Straight IPA or acetone might put spots (i.e., damage) on your dashboard, and should be used carefully. Put a little acetone, like nail polish remover, on a paper towel. This is just to wet a spot about an inch in diameter, but not enough to drip off the towel. Now rub the wet spot on your smear and see if the acetone removes it. If so, you can get the spot off. Remember to be careful with the acetone since it is a plastic solvent and might damage your dashboard if any acetone gets on it. I don’t know that it will, but it might. You can do the same with IPA, but it looks like you did already.

What year is the vehicle?
Have you been checking your coolant level? Have you had to add coolant?
Do you have a cabin air filter? Have you replaced it?

Cleaning the glass is only temporary unless you can find the source of the film.

I looked above but didn’t see anyone suggest first checking that the recirculation button on the HVAC control isn’t on. That is what this sounds like. If it is not that, I’d check that the functioning of that button is working properly and not stuck to closed. Any glass cleaner will clean glass. That is not what OP is describing (from what I can tell).

How old is this Ford Escape?

I’m thinking this might be a matter of chemicals from the dashboard out-gassing from sun exposure and getting on the inside of the windshield.

Goo Gone makes several cleaners that are designed to remove sticker gunk. I would to go the neighborhood hardware store and ask someone to recommend one of them, or a similar acetate cleaner. These are harsh chemicals, so be careful to wear rubber gloves and face/eye protection when you use them, and make sure all the doors and windows are open so you get plenty of ventilation.

The last time I used Goo Gone, it was to remove superglue from a pair of glasses. It evaporates quickly, but you’re going to want to make sure you don’t leave any behind. I’d follow up by cleaning the inside of the windshield with regular glass cleaner.

Afterwards, I’d give the dashboard a good cleaning, and then maybe buy a dashboard cover if you don’t have one already.

I wouldn’t use Rain-X on the inside of a windshield unless it’s their defogging product meant to be used on the inside, but I don’t think that is going to solve your problem.

You’d think the ink on the newspaper would get smeared onto the window if you did that. Doesn’t happen for some reason?

If it helps posters, this vehicle was a new purchase in 2012 according to the OP’s other posts. The outgassing should be over by now.

The ink (carbon black) is insoluble in just about anything.


From what I have read, the glycerine content of that ink is actually a boon to the removal of the film on the inside of the windshield.

Newspaper ink is oil based, maybe the oil in the ink helps.

I would not use ammonia. If you have a plastic film, like a tint strip, it will remove it. It will also damage many anti-glare coatings. I use a little dishwashing detergent in hot water and dish cloth to wash, then rinse with a clean dishcloth in plane water and dry with a dish towel. I make a final pass with a damp microfiber cloth. If you have also cleaned the outside of the windshield before you do the inside, then it will be like the glass disappeared.

Rain-X can be used on the inside as it also cuts trough grime and residues quite well, I have done that but I prefer the dishwashing detergent.

That residue buildup is very difficult to remove, you have to keep at it.

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Outgassing doesn’t stop, it decreases over time though. We still get a film on the windshield of our 14 year old van. I also had it on my 12 year old Accord before I sold it.


OP: are you a smoker? Seems every smoker’s car has a film on the window that apparently is damn near impossible to remove.