I used some XMT 4 on the hood of a car that I did and various other spots on the car. I spot corrected. ON the hood my pad got filled with what looked like black gunk and it is a black car I dont think that just the hood was repainted with single stage and I dont think that I burnt thru the clear as it has an even shine and alot of it. Could this black gunk be just oxidation from years of neglect. It washed out easy. Thanx