TDI (engine)

TDI (Turbocharged Direct Injection) is the Volkswagen Group's term for its current common rail direct injection turbodiesel engine range that have an intercooler in addition to the turbo compressor. TDI engines are used in motor vehicles sold by the Audi, Volkswagen, SEAT, and Škoda marques, as well as in boat engines sold by Volkswagen Marine, and industrial engines sold by Volkswagen Industrial Motor. The first TDI engine, a straight-five engine, was produced for the 1989 Audi 100 TDI sedan. In 1999, common rail fuel injection was introduced in the V8 engine used by the Audi A8 3.3 TDI Quattro. From 2006 until 2014, Audi successfully competed in the LMP1 category of motor racing using TDI engine-powered racing cars. 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. Volkswagen has admitted to using the illegal device in its TDI diesel cars.