Has anyone had success with removing tannin (tannic acid) stains caused by tree leaves sitting on their car paint finish for an extended period of time? I have searched the net and found that oxalic acid (used for cleaning and brightening wood decks & fences) is supposed to remove tannic acid stains from automobile paint finishes, but I'm reluctant to try it as I haven't found a product that lists it for this use. If anyone has found a product that works well removing tannin stains from their Fiero, could you kindly let me know? TYVM!

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Now new owner of a Black TTop 88 Fiero GT and owner of a Silver 88 Fiero GT. Also a second time owner of an 85 Fiero GT. Bought my first fully loaded Red Fiero GT new in 1985. Fiero's are Fabulous, Fix'em and have Fun! Note, Avatar picture is Mr. Bean (not me, ha ha).

I don't see anything wrong with using Oxalic acid, but polishing compound with a fine grit, say 2000, may be the first thing to try. It is designed for automotive use, and I suspect tree leaf stains are all on the surface of the clear coat.

my last car was white. The stains always came out when I clay bar it. my stains were usually minor though.

I always use rubbing compound. Never have used a claybar...guy demonstrated using it at a Griots Car Care Clinic here on one of my cars. It didnt make any difference at all. Apparently I keep my cars all to clean for it to make an improvement Really stubborn stains i swipe it lightly with some 2000 grit wet or dry. Only thing I have a problem with is birds eat the berries off one of my trees and if they take a dump on takeoff and it sets there more than a few days it eats into the paint surface. I really have to work at getting it out. One left his mark in the middle of the Sebring hood about size of a quarter and it took me an hour to get it out.

I got some Meguiars Ultimate Compound (liquid micro-abrasive compound) and applied it with a wad of cheese-cloth. I rubbed it on up and down, then side to side a few times, and finally up and down again, then polished it with a soft micro-fiber cloth and voila about 3/4 of the tannin stains were removed! I did another application the same way and virtually all of the staining was removed and the paint finish almost looks brand-new. Thankfully only the front hood and rear decklid were affected by the tannin staining as the roof is mostly glass with the T-tops, so I don't have that much to remove.

I am still leary about using paste type rubbing compound and 2000 grit sand paper (have never tried it) as I would be afraid that once I dulled the paint (clear coat) finish, I would never be able to get the shiny finish back again. I know auto body shops do this procedure, but with my luck, I would ruin the paint finish.

I hope this information is helpful to others, and a big Thank You goes out to all who responded and offered their suggestions!

Don't rub if you don't really need to. My car parks under a nasty tree that does this all the time during a season. I just pour some household bleach on (classic, Clorox brand*) , spread it with a VERY soft brush or cloth, and rinse promptly. The paint surface has never become any duller. I do a light wax wash, just in case. You may want to try it on a less visible spot first.

* for odd reasons, supermarket generic brands failed to do as good a job. Clorox acts quicker. They ingredients and concentrations are supposed to be the same!

Jdlog, Thank you for the suggestion. I will try using some bleach with a Q-Tip on a small inconspicous spot.

Has anyone else used household liquid bleach (sodium hypochlorite) such as Clorox, Javex, Old Dutch, etc. on their car paint finish?
I do have some reservations about using a caustic liquid on car paint unless further results can be supported by PFF members.

Jdlog,
I tried household bleach on a tannin stain, let it sit on the stain, and even tried to rub it in, but it did not budge. Then I used Meguiars Ultimate Compound applied with cheesecloth vertically, horizontally, and vertically again, and the stain came out completely leaving behind a nice new car shine.
Thanks for the suggestion, it was worth a try, but I'm glad Meguiars Ultimate Compound did the trick in the end.

NEXT TIME TRY CLR ..

I use bleach in garden sprayer to clean the tree sap off of my boat every spring. It works well. several of my boats have been painted not jelcoat.I have never had any problems doing this.

Another product I was going to try (it has oxalic acid as an ingredient) was Star Brite Boat Hull Cleaner.
My son brought his boat over to clean the hull with my pressure washer. We tried everything under the kitchen sink but nothing would budge the brown slime stains off the boat hull, not even with the pressure washer. He finally went to a boat dealer and picked up the Star Brite product. He sponged it on and the stains washed off immediately without any elbow grease whatsoever. It's what I should have used in the first place, but forgot all about it until after I started using the Meguiars Ultimate Compound (just another one of my frequent senior moments).