A CPU substitutes a difference between a crank-side speed that is a rotation speed of a crankshaft and a downstream-side speed that is a speed of a portion, opposite from the crankshaft, in a damper into a differential speed. The CPU calculates a torsion speed component that is a speed component of the crankshaft due to torsion of the damper based on a physical model of which an input is the differential speed, and calculates a time that is a variable indicating a speed of the crankshaft, used to determine a misfire, based on the torsion speed component. The CPU delays acquisition time of the downstream-side speed used to calculate the differential speed, with respect to acquisition time of the crank-side speed according to the rotation speed of the crankshaft.

The present disclosure relates to a method for detecting and distinguishing a cause of at least one combustion misfire of an internal combustion engine. The internal combustion engine has several cylinders, at least one exhaust gas tract, and an exhaust gas sensor which is arranged in the exhaust gas tract. The method includes the following steps: acquisition of a measurement signal with the exhaust gas sensor over a certain first period of time gas tract; subdivision of the measurement signal into measurement signal sections; assignment of the measurement signal sections to the corresponding cylinders, whereby cylinder-selective measurement signal profiles are produced that are characteristic of the respective oxygen content downstream of the respective cylinders over the determined first period of time of time; and evaluation of the cylinder-selective measurement signal profiles to detect at least one combustion misfire of the internal combustion engine.

A method for controlling an internal combustion engine with a crankshaft position sensor, intake air pressure sensor and fresh air intake throttle valve, includes: determining the engine's rotational speed based on the crankshaft position derivative relative to time; determining the intake air pressure for a first crankshaft position corresponding to 180° before top dead center; determining the intake air pressure for a second crankshaft position corresponding to 390° before top dead center; determining an atmospheric pressure learning pressure threshold based on the engine's rotational speed; determining whether the difference between the intake air pressures for the first and second crankshaft positions is below the atmospheric pressure learning pressure threshold; if so, commanding atmospheric pressure learning by applying a first-order filter to the intake air pressure for the second crankshaft position; and controlling the internal combustion engine as a function of the learned atmospheric pressure value.

The disclosure relates to an apparatus and a method for adapting control of a brushless electric motor in order to influence a position of an actuator, wherein at least two values of an output variable of a sensor are recorded in order to determine a position of the actuator, an item of information relating to the position of the actuator is determined on the basis of the at least two recorded values, the determined information relating to the position of the actuator is assigned to an item of information relating to a rotor position of the electric motor, wherein the at least two recorded values are recorded at two different times in a predefined interval of time, and wherein a duration of the predefined interval of time is determined on the basis of a characteristic of the electric motor.

A method for detecting the physical stoppage of an internal combustion engine including a crankshaft that drives a toothed wheel having a plurality of teeth, each tooth corresponding to different angular positions of the crankshaft, a sensor positioned next to the toothed wheel generates a signal characteristic of the passage of a tooth. The method detects a tooth from the signal generated by the sensor, identifies the tooth detected, triggers a timeout, and detects stoppage of the engine if the passage of a tooth adjacent to the tooth detected has not been detected before the end of the timeout. The value of the timeout is dependent on the tooth identified, and including: determining crankshaft angular position depending on the tooth identified, the value of the timeout dependent on the angular position of the crankshaft, determining the preferential stopping positions of the crankshaft and assigning a first timeout value for the preferential stopping positions and assigning at least a second value for the other positions of the crankshaft. The first timeout value being less than the second timeout value.

A method and a device for checking the functionality of a crankcase ventilation system of an internal combustion engine is provided. The system has a low-load vent line and a high-load vent line between a crankcase outlet of a crankcase and a respectively associated introduction point into an air path of the internal combustion engine, in which method and device the pressure prevailing in the crankcase is measured by a crankcase pressure sensor and is compared with a crankcase pressure modeled on the assumption of a fault-free crankcase ventilation system, and in which method and device information items regarding the presence of a fault and of an associated fault location in the crankcase ventilation system are determined from the comparison result.

A method for estimating pressure in an intake manifold of an indirect injection combustion engine. A pressure sensor measures pressure in the intake manifold, the intake manifold being in fluidic communication with a combustion cylinder, a piston guided in translation in the combustion cylinder and connected to a rotating crankshaft. The method includes: measuring, with the pressure sensor, a maximum pressure corresponding substantially to a maximum pressure in the intake manifold during a preceding cycle of the engine; measuring, with the pressure sensor, a minimum pressure corresponding substantially to a minimum pressure in the intake manifold during the preceding cycle of the engine; determining a pre-calculated average pressure correction factor from a crankshaft angular position and from an engine speed; and estimating the pressure in the intake manifold for the crankshaft angular position of the current engine cycle from the average correction factor and from the minimum and maximum pressures.

A method and system for operating a two-stroke engine includes a fuel system comprising a fuel pressure sensor, fuel temperature sensor and a fuel injector and a controller in communication with the fuel pressure sensor and fuel temperature sensor. The controller controls the fuel injector with a fuel pulsewidth determined by determining a beginning time of a window for measuring fuel pressure, determining an ending time of the window, measuring fuel pressure between the beginning time and the ending time, determining a fuel pulsewidth based on the fuel pressure and fuel temperature and injecting fuel into the two-stroke engine in response to a desired fuel mass.

A control system includes a first control device and a second control device. The second control device transmits, to the first control device, a resonance influence torque or a first motor rotation angle speed, and information acquisition timing, which is an acquisition timing of the first motor rotation angle speed. The first control device calculates an engine inertia torque based on an engine rotation angle speed. The first control device selects the resonance influence torque based on the first motor rotation angle speed acquired at a predetermined derivation timing, based on the received information acquisition timing, and derives, as an engine torque, a sum of the resonance influence torque and the engine inertia torque, calculated based on the engine rotation angle speed derived at the predetermined derivation timing.

A method for operating a control unit for an exhaust gas sensor, in particular for a broadband lambda sensor for an internal combustion engine, in particular, of a motor vehicle, or for another sensor device. The control unit is designed to electrically activate the exhaust gas sensor. The control unit is, in particular, implemented in the form of an application-specific integrated circuit (ASIC). The method includes: specifying a measuring sequence and/or a starting point in time, in particular, for an operation of the control unit and/or of the exhaust gas sensor, with the aid of a computing device.