Fuel injection is an electronic fuel delivery system that increases performance and fuel economy. It achieves this by monitoring engine conditions and providing the correct air/fuel mixture based on the engine's demand. Unlike a carburetor, which mixes fuel and air together before loading it into the intake manifold (and ultimately, the cylinder intake port), fuel injection injects the fuel directly into the combustion chamber through the cylinder head. This enables more precise control over the quantity and air/fuel mix, thus delivering optimum performance and economy. The need for a carburetor is eliminated, as well as the need for complex and imprecise tuning.