Black trim on fenders above wheel-wells
Two of the four black plastic fender trims, above the wheel-well, on my 1999 Mazda are partially discolored (about 50% of the trim) a white color -- almost like it's oxidation of the black plastic. I've tried cleaning it with some oxidation cleaner called "Back to Black" but it doesn't even phase it. Funny thing is the other two fender trims are just fine it's just the one up front by the passenger side and the other is on the back on the driver side. Weird.
Any suggestions to restore the black color to the trim?