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Todays injection systems for diesel engines work with highly sophisticated mechanical governors. But only by electronic control of diesel injection systems will it be possible to comply with the emission regulations and to achieve better performance. In 1986 BOSCH started volume production of Electronic Diesel Control (EDC). This paper will concentrate on the electronic control unit (ECU) as it was designed for use in passenger cars. The production ECU and the planned next-step ECU are outlined, explaining hardware and software. An outlook of development goals of the future EDC control-units is given.

If a sensor shall be applied in motor vehicles, all the components of the sensor must fulfil special requirements. Particular attention must be paid to the installation of the sensitive element and to the adaptation to which the sensor is to be put. The objective of this paper is to illustrate these demands more closely using three different types of sensors as examples: a displacement sensor, a pressure sensor and an acceleration sensor.

Despite the tough environmental conditions facing electronic systems in commercial vehicles, electronics is gaining ground also in these applications. In the drive sector it improves the operation of the main and auxiliary drives, upgrades fuel efficiency and reduces emission pollutant levels. It enhances safety by preventing wheel spinning in braking and acceleration. Electronic displays reduce the number of single indications otherwise needed, thus making for more clarity in information for the driver and facilitating the driver's task. Self-diagnosing and integrated emergency operation (“limp home”) capabilities are to ensure availability, a factor of special importance in commercial vehicles. A data interface standardized as widely as possible would allow add-on systems to be coupled easily and flexibly.

The VOLKSWAGEN VANAGON SYNCRO is presented as a novel 4 WD. The visco coupling is the heart of the forward drive train. Main advantages are automatic performance distribution between the axles and self-locking at extreme revolution differences between front and rear. Another important advantage of the standard 2 WD Vanagon is the well-known excellent spring suspension and damping comfort which is not negatively effected by the 4 WD technique. The vehicle is equipped with a new more powerful engine with 2,1 liter displacement and 70 kW (95 HP) nominal power output which is based on the watercooled horizontally opposed engine program. Electronic fuel injection and ignition are integrated into a unique Volkswagen system called DIGIFANTR. Vehicle performance data and fuel economy figures are given in comparison with 2 WD designs and previously available engine power train combinations.

Increasingly stringent requirements regarding exhaust emission, fuel consumption, driveability and comfort have led to an accelerated introduction of electronically controlled systems, the complexity of which can best be handled by microcomputers, these being the basis of all modern electronic control units. These electronic control units are usually installed in the passenger compartment, due to the need for moderate conditions in respect of temperature, vibration, moisture and dust. However because of the increasing variety of systems the available space for the installation of these control boxes has become smaller and smaller whilst the complexity of the wire harness has led to increased costs and electromagnetic interference problems. As a result there is an increasing demand for electronic control units (ECU) which can be installed in the engine compartment.

The usage of Electronic Diesel Control is increasing with todays stringent emissions regulations. This requirement also necessitates that such systems be versatile to meet the needs of the engine/vehicle manufacturer. EGR, start of injection, and fuel delivery can be electronically controlled. Depending on the design goals of the manufacturer any one or two of these can be controlled for partial and all of them for full Electronic Diesel Control. The development and application process has several critical areas. These include, development of the sensors, application of the different subsystems, failure warning and failure mode operation. All of these must be combined if design goals are to be met. As the capabilities of electronics increase it follows that electronic vehicle systems will also improve. Today impressive results have been achieved with systems that are in full or pilot production.

The range of Robert Bosch in-line pumps is designed for engines with cylinder outputs of up to 200 kW. Within this family of pumps the MW pump is used in small IDI engines and medium-sized DI engines with cylinder outputs in the region of 30 kW. More stringent exhaust emission legislation and the need to ensure optimum fuel economy call for efficient fuel-injection systems for diesel engines. In both of its designs the new MW pump meets these more exacting requirements and forms the contribution of Robert Bosch GmbH toward developing advanced diesel engines.