Fuel System
The fuel system pumps gas from the gas tank and mixes it with air so that the proper air/fuel mixture can flow into the cylinders. Fuel is delivered in three common ways: carburetion, port fuel injection and direct fuel injection.
  • In carburetion, a device called a carburetor mixes gas into air as the air flows into the engine.
  • In a fuel-injected engine, the right amount of fuel is injected individually into each cylinder either right above the intake valve (port fuel injection) or directly into the cylinder (direct fuel injection).
See How Fuel Injection Systems Work for more details.