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This paper describes the main strategies of the advanced Motronic MED7 engine management system for gasoline direct injection. This concept supports all required operation modes e.g. stratified, homogeneous lean and semi stratified to meet the highest fuel savings provided by the customers GDI combustion concept. Coordinated with Bosch GDI-components this system offers the highest performance for the future emission standards ULEV, EUIII and EUIV and meets all EOBD-requirements. The main structure of this system is based on the engine torque and is coordinating all activities via torque and efficiencies. The different operating modes are coordinated by a special dynamic mode manager, which is able to select the optimal operating mode under all conditions. The aftertreatment concept is based on an exhaust catalyst system comprising a fast heated pre-catalyst for early HC-reduction and a main catalyst with a NOx-adsorber anda TWC.

An effective method for detecting misfire using crank speed fluctuations has been developed for on-board use in production vehicles. Engine misfire is represented in this method by Engine Roughness identified by crankshaft rotational acceleration. Engine Roughness is calculated for each combustion event and is compared with a speed and load dependent threshold permitting the determination of single or continuous misfire. Correctional functions are applied to avoid erroneous detection during highly transient engine operation. In the wide range of engine speed and load at common driving conditions the detection of single and continuous misfire events is possible without requiring additional sensors or electronic hardware in most cases. This sophisticated method as well as other OBDII functions has already been implemented into 8 bit and 16 bit ECU's.

Misfiring of the engine can cause damage to the catalyst within short time and increase emissions. Under misfiring conditions, unburned fuel and oxygen are pumped into the catalyst, where its combustion heavily increases the temperature. For this reason there is a demand for fast detection of misfiring. Once judged, one can take countermeasures to avoid further temperature rise. Two methods of misfire detection with the prospect of future use in series production are discussed. A first approach uses the trace shape of the λ-sensor signal for evaluation. The second approach uses the speed fluctuations of the engine for detection. Efficient algorithms give the possibility of misfire detection in the full load-speed range with reasonable effort to protect the catalyst. However there will remain some misfire conditions, increasing the emissions above regulation limits, that cannot be detected by those methods.