Basic Automobile

Engine.  The engine—the "heart" of the automobile—operates on internal combustion, meaning the fuel used for its power is burned inside Karl Friedrich Benz  in his first automobile.  (Reproduced courtesy of the Library of Congress .) of the engine. This burning occurs inside cylinders, which contain pistons. The pistons are attached, via a connecting rod, to a  crankshaft . Gasoline, the most common automobile fuel, is pulled into the cylinder by the vacuum created as the piston moves down through the cylinder. The gasoline is then compressed up into the cylinder by the upward movement of the piston. A spark is introduced through a spark plug placed at the end of the cylinder. The spark causes the gasoline to explode, and the explosion drives the piston down again into the cylinder. This movement, called the power stroke, turns the crankshaft. A final movement of the piston upward again forces the exhaust gases, the byproducts of the fuel's combustion, ...