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Windshield Schmutz

I have a 2009 Hyundai Sonata. The inside surface of the windshield (and, to a lesser degree, the other glass) quickly develops a film of some sort after cleaning. This is kind of a pain, as cleaning the inside of the windshield is an unpleasant task…but of greater concern- what causes this, and what moght it be doing to our lungs?


it is gases from the materials inside the car or if it smells real sweet it could be a coolant leak inside the car.

If this film quickly reappears after cleaning, there is a very real possibility that the heater core is leaking coolant, and this is being aerosolized into the interior when the HVAC system is used.

Since this type of situation is very bad for your lungs (trust me, I know, after having developed pneumonia as a result of this problem that I did not recognize soon enough with my '86 Taurus), it is something that needs to be investigated very soon by a competent mechanic. If the heater core is leaking, be prepared for a very large repair bill, as this is the classic case of a part that costs…probably less than $50…coupled with high labor costs to remove…possibly the entire dashboard, in order to access the heater core. Potentially, this may cost…maybe $400-500 to repair.

If the heater core is not leaking, then the only other things that I can recommend are the following:

If you are using Armor-All or a similar dressing on the dashboard and other interior plastics, stop using it, and clean off the remaining gloss.
Start using a superior glass cleaner, such as Invisible Glass. This is available at Lowe’s and some other retailers, and it is not cheap, but it is VERY good. Use sheets of newspaper to wipe down the windows, rather than paper towels, as this is also a good strategy for keeping the glass clean.

Do you use Armor All???

Since your car is fairly new, I’d guess this is outgassing of the plastics used to make your car’s interior. This is a common complaint, esp w/new cars. Have you noticed this ever since the car was new? If so, that confirms it is probably outgassing. Windex will usually clean this off w/out much problem. Have you tried that?

If you are concerned about your lungs, open the windows I guess.

Try scrubbing the inside of the windshield with a crumpled up piece of newspaper. Plain black printed paper, not colored. No water, no windex, nothing but a dry piece of paper. If it cleans up and stays clean, you’re done. If the film starts to form above the defroster vents, it could be a leak in the heater core. If it forms all over at the same time, it’s probably outgassing, which is pretty common in hot weather in a newer car. If you smoke in the car (or anyone smokes in the car) then that’s the problem.