Abstract: A sensor and evaluation device configured for detecting a misfire in an internal combustion engine, the sensor and evaluation device including: a control sensor system, which includes an acceleration sensor configured for acquiring a sound measurement signal at a cylinder and for providing a knock signal assigned to the sound measurement signal; and a module configured for at least one of acquiring and evaluating the knock signal, wherein the sensor and evaluation device is configured such that: an evaluation-relevant operating cycle angle range is assigned to an operating cycle range after an exhaust valve is opened; the sound measurement signal at the cylinder is detected by the acceleration sensor at least for the evaluation-relevant operating cycle angle range, and the knock signal assigned to the sound measurement signal for the evaluation-relevant operating cycle angle range is fed to the module in an evaluable manner.

Abstract: A method for operating an internal combustion engine: detecting a first signal from a knock sensor in a temporal measurement window for a first load point and for a first energization duration—assigned to a pre-injection—of an injector for an operating cycle; calculating a first first evaluation point from the first signal by a first metric; detecting a second signal from the knock sensor in the temporal measurement window for the first load point and for a second energization duration—assigned to the pre-injection—of the injector for the operating cycle; calculating by the first metric a second first evaluation point from the second signal; determining an optimum energization duration as an optimum of the first first evaluation point and the second first evaluation point; and storing and/or applying the optimum energization duration to the first load point and the first combustion chamber.

Abstract: A method for monitoring an operation of an internal combustion engine includes the steps of: detecting, during the operation of the internal combustion engine, an acoustic signal, at least partially, during a closing process of a gas exchange valve of the internal combustion engine; evaluating, based on the acoustic signal which is detected, at least one functional state of the internal combustion engine; and selecting the at least one functional state of the internal combustion engine from a group consisting of a state of the gas exchange valve and a state of a structure-borne noise sensor used to detect the acoustic signal.

Abstract: A method for operating an internal combustion engine: detecting a first signal from a knock sensor in a temporal measurement window for a first load point and for a first energization duration—assigned to a pre-injection—of an injector for an operating cycle; calculating a first first evaluation point from the first signal by a first metric; detecting a second signal from the knock sensor in the temporal measurement window for the first load point and for a second energization duration—assigned to the pre-injection—of the injector for the operating cycle; calculating by the first metric a second first evaluation point from the second signal; determining an optimum energization duration as an optimum of the first first evaluation point and the second first evaluation point; and storing and/or applying the optimum energization duration to the first load point and the first combustion chamber.

Abstract: A method for operating an internal combustion engine. The method includes providing a piston engine. The piston engine includes a crankshaft and a torque sensor system. The torque sensor system includes at least one first rotary angle sensor and at least one second rotary angle sensor. The method further includes measuring a first and a second rotary angle in a spacing region and determining an angular offset between the first and the second rotary angle. The angular offset results from the torsion of the loaded crankshaft wherein the spacing region is limited along the crankshaft to an actual partial region of the spacing between the bearing journals. The partial region includes an actual subgroup of at least one of the number of offsets and the number of shaft journals, so that the angular offset is assigned to the actual subgroup.

Abstract: A method for operating an internal combustion engine, the method including the steps of: (a) actuating an injector to introduce a pre-injection amount of a fuel into a combustion chamber of the internal combustion engine; (b) determining, for an operating cycle of the combustion chamber in which the injector was actuated in the step (a), a pressure gradient characteristic value which is characteristic of a combustion chamber pressure gradient in the combustion chamber; (c) repeating the steps (a) and (b) a plurality of times; (d) determining a skew of a distribution of a plurality of pressure gradient characteristic values determined in the step (c); and (e) changing or maintaining an actuation of the injector depending on the skew determined in the step (d).

Abstract: A method for operating an internal combustion engine. The method includes detecting a structure borne sound signal in a time-dependent manner for the at least one combustion chamber during operation of the internal combustion engine, and determining, in a predetermined measuring window, at least one evaluation parameter from the detected structure borne sound signal. The method also includes obtaining at least one comparative result by comparing the at least one evaluation parameter with at least one predetermined comparison value, and assigning to the structure borne sound signal, on the basis of the at least one comparative result, one of a knocking event in the at least one combustion chamber and an interference signal.

Abstract: A method for operating an internal combustion engine, including aligning an injection behavior of the number of injectors. Aligning the injection behavior includes switching off one injector of the number of injectors, detecting a signal of the internal combustion engine that is to be assigned to the switched off injector, determining an alignment characteristic from the signal and assigning the alignment characteristic to the switched off injector as an alignment characteristic assigned to the injector, and switching on the previously switched off injector. Aligning the injection behavior further includes performing the aforementioned steps sequentially for the other injectors of the number of injectors and correcting a control of an injector that is to be corrected using the measured value assigned to the injector that is to be corrected.

Abstract: A method for monitoring a cylinder pressure sensor, in which method the sensor value is checked for admissibility and inadmissibility in a predefinable crankshaft angle range, when admissibility is detected the cylinder pressure sensor is used further and when inadmissibility is detected the cylinder pressure sensor is deactivated. A first sensor value of the cylinder pressure sensor is set as a start value, and a second sensor value is set as a stop value, a plateau range is determined from the number of sampling steps between the start value and the stop value, and the plateau range is set as decisive for the admissibility or inadmissibility of the sensor values.

Abstract: A method for operating an internal combustion engine, including aligning an injection behavior of the number of injectors. Aligning the injection behavior includes switching off one injector of the number of injectors, detecting a signal of the internal combustion engine that is to be assigned to the switched off injector, determining an alignment characteristic from the signal and assigning the alignment characteristic to the switched off injector as an alignment characteristic assigned to the injector, and switching on the previously switched off injector. Aligning the injection behavior further includes performing the aforementioned steps sequentially for the other injectors of the number of injectors and correcting a control of an injector that is to be corrected using the measured value assigned to the injector that is to be corrected.

Abstract: A method for operating an internal combustion engine. The method includes providing a piston engine. The piston engine includes a crankshaft and a torque sensor system. The torque sensor system includes at least one first rotary angle sensor and at least one second rotary angle sensor. The method further includes measuring a first and a second rotary angle in a spacing region and determining an angular offset between the first and the second rotary angle. The angular offset results from the torsion of the loaded crankshaft wherein the spacing region is limited along the crankshaft to an actual partial region of the spacing between the bearing journals. The partial region includes an actual subgroup of at least one of the number of offsets and the number of shaft journals, so that the angular offset is assigned to the actual subgroup.

Abstract: A method for operating an internal combustion engine. The method includes detecting a structure borne sound signal in a time-dependent manner for the at least one combustion chamber during operation of the internal combustion engine, and determining, in a predetermined measuring window, at least one evaluation parameter from the detected structure borne sound signal. The method also includes obtaining at least one comparative result by comparing the at least one evaluation parameter with at least one predetermined comparison value, and assigning to the structure borne sound signal, on the basis of the at least one comparative result, one of a knocking event in the at least one combustion chamber and an interference signal.

Abstract: A method for monitoring a cylinder pressure sensor, in which method the sensor value is checked for admissibility and inadmissibility in a predefinable crankshaft angle range, when admissibility is detected the cylinder pressure sensor is used further and when inadmissibility is detected the cylinder pressure sensor is deactivated. A first sensor value of the cylinder pressure sensor is set as a start value, and a second sensor value is set as a stop value, a plateau range is determined from the number of sampling steps between the start value and the stop value, and the plateau range is set as decisive for the admissibility or inadmissibility of the sensor values.

Abstract: The invention relates to a method for detecting the failure of injectors in an internal combustion engine, comprising the following steps: measuring a crank angle signal; transforming the crank angle signal into the frequency range by means of a discrete Fourier transformation; switching off each injector once and in a sequential manner; detecting and storing an angle of the harmonic of the 0.5th order of the Fourier-transformed crank angle signal for each switched-off injector once and in a sequential manner; continuous detection and storage of an angle and an amount of the harmonic of the 0.

Abstract: The invention relates to a method for adjusting an injection behavior of injectors in an internal combustion engine, including the following steps: switching off an injector; detecting a crank angle signal of the internal combustion engine; transforming the crank angle signal into the frequency range by way of a discrete Fourier transformation; detecting and storing a quantity of the harmonic of the 0.5th order of the Fourier transform of the crank angle signal, and assigning the quantity to the switched-off injector; switching on the switched-off injector; performing the previous steps sequentially for all injectors of the internal combustion engine; forming an average value of the stored quantities with respect to all injectors, and correcting the control of the injectors using a deviation from the average value of a quantity associated with an injector that is to be corrected.

Abstract: A method for torque control of an internal combustion engine includes a pressure sensor that is associated with at least one, but at the most two cylinders of the internal combustion engine, whereby an cylinder internal pressure for the cylinder associated with the pressure sensor is detected. The method carries out an adjustment of injection characteristics for the injectors allocated to the individual cylinders of the internal combustion engine by way of a method which is independent from the detected cylinder pressure. A torque control for the internal combustion engine is performed based on the detected cylinder pressure.

Abstract: A method and an arrangement for monitoring an exhaust system of an internal combustion engine. Temperature profiles upstream and downstream of an installation location of a catalytic converter are measured in order to determine whether or not a catalytic converter is installed.

Abstract: The invention relates to an operating process for a lean-burn gas engine having several cylinders, wherein the lean-burn gas engine includes a cylinder-individual gas metering arrangement and a cylinder-individual combustion process capture. The lean-burn gas engine is controlled by a control unit in such a manner that a combustion duration of the individual cylinders is regulated by a control unit, by way of a change of ignition timing of the individual cylinders. The control unit regulates the ignition timing of the individual cylinders in such a way that all cylinders are equalized in regard to their turnover point, so that a defined turnover point is achieved at a defined crank shaft angle.

Abstract: A method for operating a reciprocating-piston internal combustion engine, including: supplying a fuel mixture having two fuel types and air into a combustion chamber; burning the fuel mixture in the combustion chamber during a working stroke; detecting the pressure profile in the combustion chamber during the working stroke by one pressure sensor per combustion chamber; determining an amount of energy per working stroke and per combustion chamber from the pressure profile. In order to enable different fuel types and/or fuel qualities to be taken into consideration in the regulation of the engine, the calorific value of the fuel mixture per working stroke and per combustion chamber is determined from the volume and/or the mass of the supplied fuel mixture and from the determined amount of energy per working stroke and per combustion chamber. At least one parameter of the engine is regulated as a function of the calorific value.

Abstract: The invention relates to a method for detecting the failure of injectors in an internal combustion engine, comprising the following steps: measuring a crank angle signal; transforming the crank angle signal into the frequency range by means of a discrete Fourier transformation; switching off each injector once and in a sequential manner; detecting and storing an angle of the harmonic of the 0.5th order of the Fourier-transformed crank angle signal for each switched-off injector once and in a sequential manner; continuous detection and storage of an angle and an amount of the harmonic of the 0.