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Strange film on windshield

We see a strange film on the outside of the windshield that is most visible on high humidity days and/or when raining.
Cleaning with Windex does not help

A leaking heater core will do that. Has the coolant level gone down?

It’s on the outside.
Do you ever get it wet from sprinkler systems? We had some house windows that were exposed to city water supplied lawn sprinklers that did something similar. Nothing would remove it, it was like the glass was etched. Can you feel the difference dragging a finger nail across the clear versus fogged areas? You might try using some white vinegar solution in case it is just mineral deposits left to dry on the glass exterior…


Outside. I missed that! There are pastes for cleaning windshields - maybe that would help. It might be worth stopping by an auto glass shop and asking their advice.

what is the history of the car?
did you just get it and have this problem, or you have this car and problem appeared lately?
after what?

something like this film may be a result of improperly applied glass treatments like Rain-X or similar

if it is indeed the improperly applied Rain-X, you need something like this:

you really have to apply some elbow grease to get old water repellent out, then use Windex to make it sparky-clean, and only after that to reapply repellent

even if you did not use water repellent, this paste will make your glass much smoother and liekly will eliminate any film you have

There is always the Barkeeps Friend… Bon Ami powder. It is a scouring powder that won’t scratch glass but it is great at cleaning films and deposits off glass. Sprinkel a little on damp towel and use that to rub the glass. Wipe off after it dries with a clean damp micro-fiber cloth.

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I’d try cleanings with isopropyl alcohol and white vinegar (separately), making sure not to touch anything but the glass.

This may be of some help. We tried a number of things to remove stains from auto glass. Here’s what worked for BestRide.

It’s almost like the surface of the glass is fogging up. Try this: Dissolve a little bit of pure soap (e.g. Ivory bar soap) in a glass of warm water, then use that to clean a small section of the windshield. Don’t rinse. That’s what we did in Colorado to prevent out ski goggles from fogging. If that helps, you know what to do next. I’ve used home-made apple-cider vinegar to clean glass of hard water deposits, which is another possible explanation. That works pretty good, so if the soap doesn’t work, apple cider vinegar is probably worth a try. Windshield wipers that are near the end of their service life can cause that problem too.

Thanks for your reply
It’s on the outside

Thanks, I’ll look int o the Rain-X issue