Diesel engines are becoming ever more interesting for use in motor vehicles. They are traditionally known for fuel economy and long service life. In the past few years they have now become more powerful, quieter and cleaner. Here, the fuel-injection system has played a decisive role.
     Diesel fuel-injection systems from Bosch have been a major contributor to a resurgence
of diesel engines embracing every automotive sector, including the high-speed engines employed in passenger cars. The rotary, or distributor injection pump, has been the prime mover behind diesel propulsion for a number of years. This pump's inherently immense precision allows it to meter exactly the correct fuel dosage, even in minute inject-fuel quantities. Continuous evolution has spawned control racks and electronic control systems that contribute to the diesel car’s smooth, spontaneous performance and supremely sensitive response.
When the VP44 radial-piston high-pressure pumps fitted with a high-pressure solenoid valve was launched in 1996, it opened up a range of new opportunities, for example pre-injection to reduce noise or regulating injected-fuel quantity to individual cylinders to achieve torque control. In 1998 the solenoid-valve-controlled axial-piston distributor pump appeared on the scene. The electronic control unit integrated in the pump created a system that links technological innovation to low system costs.
      This Bosch Yellow Jacket booklet from the "Expert Know-How on Automotive Technology" series deals with the design and construction of port-controlled and solenoid-valve-controlled distributor injection pumps and how their components interact within the system.
      The section on workshop technology provides insights in testing and tuning these
fuel-injection systems.
      The basics of “Diesel-Engine Management” and “Electronic Diesel Control EDC”
are described in detail in separate booklets.