Abstract: A method for determining the atmospheric pressure on the basis of the intake pressure measured downstream of an air filter in an intake line of an internal combustion engine, and of the air mass flow rate measured downstream of the air filter, and optionally of the intake air temperature. The calculation of the atmospheric pressure and the calculation of a degree of contamination of the air filter are separated by standardizing the measured air mass flow rates at two predefined values. Furthermore, during the calculation a characteristic curve for the degree of contamination of the air filter as a function of the determined pressure difference at the predefined air mass flow rates is used, and a characteristic diagram for the degree of contamination of the air filter as a function of the standardized air mass flow rate and of the determined pressure difference is used.

Abstract: A method for determining the atmospheric pressure on the basis of the intake pressure measured downstream of an air filter in an intake line of an internal combustion engine, and of the air mass flow rate measured downstream of the air filter, and optionally of the intake air temperature. The calculation of the atmospheric pressure and the calculation of a degree of contamination of the air filter are separated by standardizing the measured air mass flow rates at two predefined values. Furthermore, during the calculation a characteristic curve for the degree of contamination of the air filter as a function of the determined pressure difference at the predefined air mass flow rates is used, and a characteristic diagram for the degree of contamination of the air filter as a function of the standardized air mass flow rate and of the determined pressure difference is used.

Abstract: An internal combustion engine has a plurality of cylinders which are arranged in two rows, two exhaust-gas turbochargers which are driven in each case by the exhaust gases from the cylinders of a cylinder row, and exhaust-gas recirculation. Two exhaust-gas discharge lines branch off, upstream of the respective exhaust-gas turbocharger, part of the exhaust gases from the cylinders of a cylinder row to be recirculated and supply this part to a common recirculation line. By way of the common recirculation line, the exhaust gases to be recirculated are supplied, downstream of the exhaust-gas turbochargers, to an air supply. At least one valve, which serves as an exhaust-gas recirculation valve and by which the quantity of recirculated exhaust gases can be set, is provided. The valve has a stop by which a communicating connection made between the two exhaust-gas discharge lines can be shut off.

Abstract: A system for automatic charging pressure control using an exhaust gas turbocharger with a variably adjustable turbine cross-section and for automatic exhaust gas recirculation control in the case of an internal-combustion engine, particularly a diesel engine. An automatic control system has a first controller which has an output for the variation of the turbine cross-section of the exhaust gas turbocharger. The command variable for the automatic exhaust gas recirculation control in a first low load-rotational speed range is the air flow rate in the intake pipe. The command variable for the automatic charging pressure control in a second higher load-rotational speed range is the charging pressure in the intake pipe. For the automatic exhaust gas recirculation control, an exhaust gas recirculation pipe connects the exhaust gas pipe with the suction pipe.

Abstract: The invention relates to a method of operating a diesel engine having an engine controller which controls the operation of the diesel engine as a function of characteristic maps and permits rich/lean control of the diesel engine. The engine controller includes a computer which effects a changeover to rich or lean operation of the diesel engine as a function of predetermined changeover criteria, a sensor system which communicates with the computer and monitors parameters needed for changeover criteria, and a memory which communicates with the computer and in which the characteristic maps for operating the diesel engine are stored. The computer effects a changeover from lean to rich operation when all the changeover criteria in this respect are satisfied, and effects a change back from rich to lean operation when at least one of the changeover criteria in this respect is satisfied.

Abstract: A system and a process for operating a diesel engine using an automatic engine control which, as a function of characteristic diagrams, automatically controls the operation of the diesel engine and permits an automatic rich/lean controlling of the diesel engine. The automatic engine control includes a computer which, as a function of predetermined change-over criteria, causes a change-over to the rich or the lean operation of the diesel engine. A sensor system communicates with the computer and monitors the parameters necessary for change-over criteria. A memory communicates with the computer, the memory storing separate characteristic diagrams for the operation of the diesel engine for the lean operation and for the rich operation.

Abstract: In an apparatus for controlling a Diesel engine with exhaust gas recirculation and intake air throttling a control circuit is provided by which the intake air flow pressure is controlled by means determining the desired intake air pressure for intake air throttling operation. During operations utilizing charge air the charge air pressure is controlled by means determining a desired intake air pressure representing the sum of a desired engine operating point-dependent base pressure value and a desired supplemental pressure value which comprises the product of a desired supplemental raw pressure value which is dependent on engine speed and a fresh intake air mass flow control difference and a factor which depends on the opening degree of the exhaust gas recirculation control number.