When water evaporates on the paint of the car, the calcium and metals in tap water leave behind water spots. Car owners avoid water spots by drying the car immediately after washing or using a detailing spray to quickly remove them, but sometimes water spots are able to dry and a process involving a mild acid is needed for its removal.
The acid bath used to remove water spots can be done at home or professionally. In order to do it at home, one should first wash their car with regular shampoo and rinse, then wipe distilled white vinegar onto the car with a sponge. After letting it sit for 30 to 60 seconds, one should rinse the vinegar off of the car. After applying the vinegar section by section on every part of the car, one should again wash and rinse the car in normal fashion.
If water spots remain on a car longer than a few days, minerals in the water will leave dimples in the paint of the car. At this point, one must use the vinegar treatment to remove the surface stains before applying a dual-action car polisher to the paint with a foam cutting and polishing pad.