<P> Turbocharged direct injection or TDI is a design of turbodiesel engines featuring turbocharging and cylinder - direct fuel injection that was developed and produced by the Volkswagen Group (VW AG). These TDI engines are widely used in all mainstream Volkswagen Group marques of passenger cars and light commercial vehicles made by the company (particularly those sold in Europe). They are also used as marine engines in Volkswagen Marine and Volkswagen Industrial Motor applications . </P> <P> TDI engines installed in 2009 to 2015 model year Volkswagen Group cars sold through 18 September 2015 had an emissions defeat device, which activated emissions controls only during emissions testing . The emissions controls were suppressed otherwise, allowing the TDI engines to exceed legal limits on emissions . VW has admitted to using the illegal device in its TDI diesel cars . </P>

What does tdi stand for in vw jetta