Yes, if you do not take care of a few finer points. When your car's paint is already chipping, using a higher PSI can damage it further and may pressure it to peel off further. Also, it is essential that you remove any hard debris beforehand before using a pressure washer. When combined with hard pressure, this debris can cause scratches on the car. Once your paint is scraped and water penetrates, it starts rusting, which isn’t good.