Many of us get stuff on our cars, which will not easily come off. There is tree sap, over spray, bird droppings, rust spots and even salt marks from that stuff they put on the roads in winter; none of which is very easy to get off. It is very important for the protection of your car's clear coat and paint finish to pay careful attention when cleaning your car to remove the fallout and small Rust Spots.
You should be careful if you go to a coin-op car wash or if you use a pressure washer. It is possible to get too close to the paint and damage the finish. Generally if you blast thru a clear coat you will notice it is because there will be a pealed mark and you will rip off a large chunk of paint. Use the "one-foot rule” and keep the nozzle at least one foot away from the paint at all times. You should be fine, just remember the 1-foot rule and that also applies to center caps on rims. But the rest of the rims and tires you can get closer.
The best way to remove such contaminants
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