The same water you use to bathe your car can also damage your car's paint. The spots and damage are caused by the minerals in the water. When water evaporates off of your car's paint, it leaves behind the trace elements it contains. Calcium and metals are the most damaging ingredients found in your tap water. Rainwater may contain damaging acids from air pollutants.

Getting rid of water spots is easy if you chase after them. The best solution is to use a quick detailing spray after you wash, or as soon as you discover the spots (i.e., when your neighbor's sprinkler gets you).

If the spots are allowed to dry and bake on, they will attach to and harden on your paint. When this happens, you need to use a mild acid to get them loose. Believe it or not, the best acid is also the least expensive and most available: a gallon jug of distilled white vinegar.

Expert car detailers have known this secret for years. If you take your car to a pro, they will tell you about the "magic acid bath" and charge you $60 or more for the pleasure of smelling like a pickle. Save the $60. Put on some gloves and get to it.

To give your car the magic acid bath, first wash your car with your normal car shampoo, rinse, and then use the distilled vinegar. Just wipe it on with a sponge, and rub it in. Do one section at a time. Let it sit 30 to 60 seconds, and then rinse. When you're done, wash the car again with shampoo, and then rinse. By the way, vinegar will remove your wax, so be prepared to re-wax your car after the vinegar treatment.

If water spots are allowed to stay for more than a week or so, the minerals will etch the paint. In this case, using vinegar will remove the mineral spots, but the paint will have etched spots (dimples). It is necessary to use a polish or mild polishing compound to restore the paint surface.