 was sold with turbo direct injection in 1987 and one year later Austin Rover Montego.What was pioneering about the Audi 100, however, was the use of electronic control of the engine, as the Fiat and Austin had Bosch mechanically controlled injection.In the writers experience the Audi 100 TDI was very troublesome and the engine code "AAT" is often known as the difficult Audi .