Buying a car typically costs a lot of money, but actually owning a car can cause the biggest case of sticker shock. Are you following me here? You might get a fantastic deal on a high-performance sports car, but you'd better hang on to the money you saved. Just keeping a car on the road means paying for maintenance, insurance and of course, fuel. When you get down to it, buying a car is relatively cheap compared to owning one -- unless you're planning on letting your new wheels just sit in your garage, never to touch asphalt.
If there's one thing you can save on when it comes to owning a car, its gas. Everyone has their favorite method. Some obsessively track gas prices around town and only buy from the cheapest stations. Others use the lowest grade fuel they can get away with. Still others (mainly the people I seem to get trapped behind) alter their driving habits and attempt to hypermile -- trying to squeeze the most distance from every last drop of gasoline.
Then there are the people who try aftermarket products to improve their gas mileage.
Maybe you're an insomniac and you've seen some of these products advertised on late night TV. Usually, the product claims that by adding it to your gasoline or attaching it to your car, you'll somehow improve your car's fuel efficiency and gas mileage, saving money in the process. It's temping. The less money you spend on gas, the more money you have to spend on Cheetos, right? But, how can you know that the gas-saving product you ordered in a sleep-deprived stupor will actually live up to its promises? That's where the EPA comes in.