Audi, the inventor of TDI, is preparing to launch a diesel offensive in the North American market. The brand with the four rings will introduce the world’s cleanest diesel to the U.S. market in early 2009, almost simultaneous with its introduction in Europe. The 3.0 TDI with its ultra low emission system, which fulfills the world’s most stringent emission standards, will first be offered in the Audi Q7 and then in the new Audi A4 at a later date.