How Do Diesel Cars Work?
Diesel vehicles are similar to gasoline vehicles because they both use internal combustion engines. One difference is that diesel engines typically use a compression-ignited injection system rather than the spark-ignited system used by most gasoline vehicles. In a compression-ignited system, the diesel fuel is injected into the combustion chamber of the engine and ignited by the high temperatures achieved when the gas is compressed. Unlike the emission control systems on gasoline vehicles, many diesel vehicles also have a selective catalytic reduction (SCR) system that stores and injects diesel exhaust fluid into the exhaust stream to break down dangerous NOx emissions into harmless nitrogen and water. Diesel is a common transportation fuel and several other fuel options use similar engine systems and components. Learn about alternative fuel options.
Key Components of a Diesel Car
Battery: The battery provides electricity to start the engine and power vehicle electronics/accessories.
Diesel exhaust filler: This port is for filling the diesel exhaust fluid tank.
Electronic control module (ECM): The ECM controls the engine's performance, fuel efficiency, and emissions; safeguards the engine from abuse; monitors the operation of the vehicle; and troubleshoots mechanical problems.
Fuel filler: A filler or "nozzle" used to add fuel to the tank.
Fuel line: A metal tube or flexible hose (or a combination of these) allows for transferring fuel from the tank to the engine's fuel injection system.
Fuel pump: A fuel pump transfers fuel from the tank to the engine's fuel injection system via the fuel line.
Fuel tank (diesel): Stores fuel on board the vehicle until it's needed by the engine.
Internal combustion engine (compression-ignited): In this configuration, fuel is injected into the combustion chamber and ignited by the high temperature achieved when a gas is greatly compressed.
Selective catalytic reduction: The selective catalytic reduction (SCR) system injects diesel exhaust fluid through a special catalyst into the exhaust stream of a diesel engine to break down dangerous NOx emissions into harmless nitrogen and water.
Transmission: The transmission transfers mechanical power from the engine and/or electric traction motor to drive the wheels.