How Do Diesel Cars Work Using Biodiesel?

Biodiesel and conventional diesel vehicles are one in the same. They have the same internal combustion engine and components. Although all diesel vehicles can use biodiesel, some OEMs do not approve the use of higher-level blends of biodiesel. Before using biodiesel, be sure to check your OEM engine warranty to ensure that higher-level blends of this alternative fuel are approved. B5 (a blend of 5% biodiesel and 95% diesel) is commonly used in fleets and approved for use in all diesel vehicles. Learn more about diesel vehicles using biodiesel.

Key Components of a Biodiesel 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 (biodiesel): A fuel tank 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.


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