"Hearst Magazines and AOL may earn commission or revenue on some items through these links." This article was updated with new information in May 2026. Sometimes, the biggest nemesis of a pristine vehicle is Mother Nature. Whether it's tree sap, bird droppings, ice, or some other malady, she's an expert at spoiling your perfectly clean car. However, you can counter her attacks. One of the best defenses is a good car cover, and these are useful even if your ride lives indoors.