My experience with hard water spots on my car windows.
I had parked my new car in our driveway, next to the grass. (I’m unable to park in a garage or anywhere else.) In the morning, I did not notice the water spots on the car, because it had been raining off and on for a few days. However, after a period of no rain, the water droplets were visible, on the front and side windows of my car. Apparently, our associations’ sprinklers had come on late, the night before. Somehow, this sprinkler head was turned towards my car and with the rain and morning dew, no one noticed.
What I tried next.
The spots did not come off with window cleaner. They were still there after I had applied straight vinegar and hard rubbing, with paper towels. Nothing happened after laying vinegar soaked towels on the front window for 30 minutes. Dried with a soft cloth or paper towel. Frustrated, that I could actually feel the etching by taking my fingernail and gently scratching the glass. I knew long-term spotting ruins glass, but this was a new car with only a few days of exposure from sprinklers, mixed with rain!
I got professional advice.
Next, I had a mobile car detailer look at the spots. He said he was certified and insured for damages from his handiwork. In his opinion, the only way to be rid of the spots was to use an acid.The plan was to first wash my car, apply acid to remove the spotting, from the windows only. Then he would wax the whole car for his discounted fee of $250! However, I did not want to take a chance that my new car’s paint job might be ruined, should it be damaged from acid runs or drips, on the car’s body. Insured or not. I would still need to deal with issues of time and possibly the cost to correct whatever the end result might be. I don’t believe the detailer’s insurance coverage would pay for a new paint job on my new car! My husband thought, maybe, if I tinted my windows, that tint company might fix the problem. Or, possibly the tint might reduce or mask the water spots. Well, I can not tint the front windshield! Also, if I did tint the side windows, I might have the same water issue again, only this time, stains on plastic film. I’m sure the tinted film would not respond well if harsh chemicals were applied.
Back to the internet for more advice.
I first located a small inconspicuous, area in the bottom corner of my windshield, by the wiper. As advised, I wet the steel wool with water and made little circular motions, with a very light touch and dried with a paper towel. The glass in that area was black. This made it easy to see the spots, before and after, with the sun shining on the window. Wow! It seemed to work! Very few spots were left in one small area. They were completely gone everywhere else!
But I wasn’t ready to really go for it, on the more visible areas, just yet. I next tried this on a small area of chrome molding, next to the windshield. Also, with a light touch. Success again!
Careful now. Easy does it!
Next, I experimented on the window wiper arm, which was painted black and attached to the windshield. Again, with very light strokes. Nope! It slightly scratched the paint. I thought this might happen.
However, being the perfectionist I sometimes tend to be, I didn’t give up. I tried again, ever so lightly, on the black painted areas, on the front and back doors, between the side windows. This is where the front door opens, adjacent to where the back door is hinged. Spots really showed up there. Unfortunately, spots were gone, but slight scratches were visible.
Maybe a car wax might help painted trim? Possibly a waterless car wash spray for windows? Any ideas? Please advise me. I’m going to try these and will update my results.