See my blog on automobile
If you start waxing over the grit, it could scratch your car. Move your car to a shady spot to wax. Do not attempt to do this on a frigid day, as your labors will not yield much success. Use a non abrasive sponge or cloth to apply the car wax in circular motions. It is best to apply the wax in sections, so you can tell where you have been.