TDI stands for Turbocharged Direct Injection and a registered trademark of Volkswagen AG for its diesel engines. That means turbocharged with direct diesel injection into the combustion chamber. Compared to prechamber or swirl chamber diesel engines they are characterised by superior efficiency and thus higher performance with lower consumption.

All TDIs have electronic engine management via edc or control unit from delphi . TDI engines are installed in vehicles from Audi, Cupra, Seat, Skoda and VW.