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Gasoline Direct Injection (GDI) engines can play an important role in future powertrain concepts. They show potential for enhanced fuel economy and at the same time fulfill demands for higher specific power output. For a successful placement in the NAFTA market especially against other competing concepts such as the gasoline port fuel injection engine and the Diesel engine, GDI has to demonstrate its ability to meet existing and future emission legislation. This contribution demonstrates GDI as a low emission concept. It proposes a reliable and efficient cold-start strategy called “High-Pressure Stratified Start”. Fuel is injected by means of increased fuel pressure during compression stroke instead of the conventional start with low-pressure fuel injection during intake stroke. Consequently, mixture preparation is greatly enhanced and wall wetting is reduced. The high-pressure start produces less unburned hydrocarbon emissions and enhances start reliability at low temperatures.

Due to the social and legal requirements on the engine and the entire vehicle the functional scope of modem Engine Management Systems (EMS) has dramatically grown. As driving forces of this ongoing process the reduction of fuel consumption and emissions have to be considered - in the past as well as in the future. But also increasing comfort and diagnosis demands lead to a further increasing complexity of today's and future EMS. In order to securely control this complexity a well structured functional architecture in combination with physically based functions forms the necessary basis. With the launch of the MOTRONIC ME7 Bosch introduced a torque based functional architecture to meet these requirements. This includes not only the mentioned optimization of engine performance and compliance with legal standards on emission, fuel consumption and diagnosis.