At Volkswagen, TDI refers to diesel vehicles with direct injection and turbo charging. TDI engines are characterised by high levels of tractive power (torque) and and very good performance yield. TDI is a registered trademark of Volkswagen AG in many countries.

How it works:
a turbocharger supplies the engine with fresh air, ensuring optimum filling of the cylinder. After compression, the diesel fuel is then directly injected into this using a nozzle at a very high pressure. Effective engine encapsulation also enables quiet operation.

See also:
Direct injection