There are a few things you can do to remove oil spots from a car exterior. The first is to clean the area with a mild soap and water. This will remove any built-up dirt and grease that may have been on the surface. Next, use a hairdryer to dry the area completely. This will remove any oils that may have been left on the surface. Finally, use a vacuum cleaner and bucket to suck up all of the liquid that has been removed from the area. This will clean and dry the area completely.