Abstract: In a method, dynamic pressure oscillations in the intake tract or outlet tract of a respective internal combustion engine are measured during normal operation, and from these measured oscillations, a corresponding pressure oscillation signal is generated. A crankshaft phase angle signal is determined at the same time. From the pressure oscillation signal, an actual value of at least one characteristic of at least one selected signal frequency of the measured pressure oscillations in relation to the crankshaft phase angle signal is determined, and the current trimming of the intake tract is determined on the basis of the determined actual value, taking into consideration reference values of the corresponding characteristic of the respectively identical signal frequency for different trimmings of the intake tract.

Abstract: Various embodiments include a method for detecting deviations occurring in the valve drive of an internal combustion engine comprising: measuring dynamic pressure oscillations of intake air in an air intake tract of respective internal combustion engine during operation; calculating an inlet valve stroke phase difference and/or an outlet valve stroke phase difference based on the measured dynamic pressure oscillation; calculating a valve stroke phase deviation value with respect to a valve stroke phase reference value based on the calculated phase difference; and calculating a first valve drive deviation value based on the valve stroke phase deviation value.

Abstract: In the method according to example embodiments, dynamic pressure oscillations in the inlet tract of the respective internal combustion engine are measured during normal operation, and from these a corresponding pressure oscillation signal is generated. A crankshaft phase angle signal is acquired at the same time. The pressure oscillation signal is used to determine an actual value of at least one characteristic of at least one selected signal frequency of the measured pressure oscillations in relation to the crankshaft phase angle signal, and the current compression ratio is determined on the basis of the determined actual value and using reference values of the corresponding characteristic of the respective same signal frequency for different compression ratios.

Abstract: In a method, dynamic pressure oscillations in the intake tract or outlet tract of a respective internal combustion engine are measured during normal operation, and from these measured oscillations, a corresponding pressure oscillation signal is generated. A crankshaft phase angle signal is determined at the same time. From the pressure oscillation signal, an actual value of at least one characteristic of at least one selected signal frequency of the measured pressure oscillations in relation to the crankshaft phase angle signal is determined, and the current trimming of the intake tract is determined on the basis of the determined actual value, taking into consideration reference values of the corresponding characteristic of the respectively identical signal frequency for different trimmings of the intake tract.

Abstract: In the method according to example embodiments, dynamic pressure oscillations in the inlet tract of the respective internal combustion engine are measured during normal operation, and from these a corresponding pressure oscillation signal is generated. A crankshaft phase angle signal is acquired at the same time. The pressure oscillation signal is used to determine an actual value of at least one characteristic of at least one selected signal frequency of the measured pressure oscillations in relation to the crankshaft phase angle signal, and the current compression ratio is determined on the basis of the determined actual value and using reference values of the corresponding characteristic of the respective same signal frequency for different compression ratios.

Abstract: Various embodiments include a method for operating an internal combustion engine wherein the compression is variably adjusted comprising: checking a sensor signal indicative of a compression of the engine; checking the plausibility of the signal by: ascertaining a series of corresponding values of the signal and values of the actuating variable; determining a mathematical relationship between the signal and the variable based on the series; determining a deviation between the relationship and a predetermined characteristic relationship; and determining the signal is plausible when the determined deviation is lower than a predetermined threshold value; and if the determined deviation is higher than the predetermined threshold value, adjusting operation of the internal combustion engine.

Abstract: Various embodiments include a method for detecting deviations occurring in the valve drive of an internal combustion engine comprising: measuring dynamic pressure oscillations of intake air in an air intake tract of respective internal combustion engine during operation; calculating an inlet valve stroke phase difference and/or an outlet valve stroke phase difference based on the measured dynamic pressure oscillation; calculating a valve stroke phase deviation value with respect to a valve stroke phase reference value based on the calculated phase difference; and calculating a first valve drive deviation value based on the valve stroke phase deviation value.

Abstract: Various embodiments include a method for operating an internal combustion engine wherein the compression is variably adjusted comprising: checking a sensor signal indicative of a compression of the engine; checking the plausibility of the signal by: ascertaining a series of corresponding values of the signal and values of the actuating variable; determining a mathematical relationship between the signal and the variable based on the series; determining a deviation between the relationship and a predetermined characteristic relationship; and determining the signal is plausible when the determined deviation is lower than a predetermined threshold value; and if the determined deviation is higher than the predetermined threshold value, adjusting operation of the internal combustion engine.

Abstract: The disclosure relates to internal combustion engines in general, and teaches various methods and apparatus for operating engines with an exhaust-gas turbocharger. Some embodiments include a method for operating an internal combustion engine having a fresh-gas tract for the supply of fresh gas to a cylinder, and an exhaust tract for the discharge of exhaust gas. They may include determining a value of a first operating condition of a catalytic converter arranged in the exhaust tract; determining a value of a second operating condition of the catalytic converter; calculating, as a function of the determined value, a first value for a maximum admissible scavenged-over quantity of fresh gas into the exhaust tract during scavenging operation; and setting the maximum admissible scavenged-over quantity to a second value lower than the first value if the value of the second operating condition reaches a predefined value.

Abstract: The disclosure relates to internal combustion engines in general, and teaches various methods and apparatus for operating engines with an exhaust-gas turbocharger. Some embodiments include a method for operating an internal combustion engine having a fresh-gas tract for the supply of fresh gas to a cylinder, and an exhaust tract for the discharge of exhaust gas. They may include determining a value of a first operating condition of a catalytic converter arranged in the exhaust tract; determining a value of a second operating condition of the catalytic converter; calculating, as a function of the determined value, a first value for a maximum admissible scavenged-over quantity of fresh gas into the exhaust tract during scavenging operation; and setting the maximum admissible scavenged-over quantity to a second value lower than the first value if the value of the second operating condition reaches a predefined value.

Abstract: A method for adapting a preset value for a minimum valve stroke in an internal combustion engine, has the following steps: Replace the previous value for the minimum valve stroke with a new value; Determine an operating parameter of the internal combustion engine; Restore the previous value for the minimum valve stroke if the operating parameter is outside of a defined value range; otherwise retain the new value.

Abstract: In a method for controlling an internal combustion engine comprising an intake pipe and a throttle valve that is arranged therein, the pressure in the intake pipe is regulated by modifying the opening angle of the throttle valve, and the desired pressure value is adjusted when the valve lift of the internal combustion engine changes. An apparatus for controlling an internal combustion engine has a mechanism for regulating the intake pipe pressure, the mechanism allowing the opening angle of the throttle valve to be influenced as a controlled variable. In addition, at least one device is provided for changing the valve lift of the internal combustion engine while a device is provided for adjusting the desired pressure value to the valve lift.

Abstract: An internal combustion engine (30) with a supercharger device (50, 52) for increasing the charging pressure in an air inlet system (33) has a number of cylinders (32). Each cylinder (32) has at least one exhaust valve (36) which is connected to the exhaust system (40) and at least one inlet valve (34), which is connected to the air inlet system (33). Scavenging is carried out with a valve overlap between the inlet valve (34) and the exhaust valve (36). For controlling the operation of the internal combustion engine the system monitors whether the scavenging was successful.

Abstract: A method for determining the trapping efficiency and/or a scavenging air mass of an internal combustion engine has the steps of: for operating points (BP), in which a scavenging of a cylinder of the internal combustion engine with air takes places, an efficiency curve (?KL, ?KL,M1) of the internal combustion engine is created as a function of an injection mass (mK) of fuel in the cylinder, and on the basis of the efficiency curve (?KL, ?KL,M1) an optimum injection mass (mK,opt) for an optimum efficiency (?opt,1) of the internal combustion engine is determined, which is a measure for the trapping efficiency and/or a measure for the scavenging air mass of the internal combustion engine.

Abstract: In a method and a device for operating an internal combustion engine with a fuel pump, which on the drive side is coupled with a camshaft or a crankshaft, and a fuel accumulator, which is supplied by the fuel pump and to which a pressure sensor is assigned for sensing the pressure in the fuel accumulator, to each cycle of the internal combustion engine a first and a second crankshaft rotation (CRK_R1, CRK_R2) are assigned. Depending on a signal sequence (P_F_S) of the sensed pressure in the fuel accumulator which is characteristic of the respective crankshaft rotation it is ascertained whether the crankshaft is in its first or second rotation (CRK_R1, CRK_R2).

Abstract: In a method for controlling an internal combustion engine comprising an intake pipe and a throttle valve that is arranged therein, the pressure in the intake pipe is regulated by modifying the opening angle of the throttle valve, and the desired pressure value is adjusted when the valve lift of the internal combustion engine changes. An apparatus for controlling an internal combustion engine has a mechanism for regulating the intake pipe pressure, the mechanism allowing the opening angle of the throttle valve to be influenced as a controlled variable. In addition, at least one device is provided for changing the valve lift of the internal combustion engine while a device is provided for adjusting the desired pressure value to the valve lift.

Abstract: In a method and a device for controlling a pump (14, 20) connected to a fuel rail (12) in an internal combustion engine, in order to provide a predetermined quantity of fuel in the fuel rail (12) for a predetermined operating state, the following steps are provided: determining whether a process occurs that switches the internal combustion engine into a next predetermined operating state; determining a pump output of the pump (14, 20) if the process for switching the internal combustion engine into a predetermined operating state was detected, whereby the pump output of the pump (14, 20) is selected such that the predetermined quantity of fuel is provided for the operating state; and actuating the pump (14, 20) so that the pump (14, 20) provides the predetermined quantity of fuel when the predetermined operating state is reached.

Abstract: A method for controlling an internal combustion engine with variable valve lift has the following steps: Determining the pressure in the intake manifold; predetermining the pressure in the intake manifold following a changeover of the valve lift; determining a selection criterion for a valve lift to be set; and setting that valve lift at which the higher pressure is reached in the intake manifold, unless the selection criterion requires the use of the valve lift at which the lower pressure is reached in the intake manifold.

Abstract: In a method and a device for operating an internal combustion engine with a fuel pump, which on the drive side is coupled with a camshaft or a crankshaft, and a fuel accumulator, which is supplied by the fuel pump and to which a pressure sensor is assigned for sensing the pressure in the fuel accumulator, to each cycle of the internal combustion engine a first and a second crankshaft rotation (CRK_R1, CRK_R2) are assigned.

Abstract: A method for adapting a preset value for a minimum valve stroke in an internal combustion engine, has the following steps: Replace the previous value for the minimum valve stroke with a new value; Determine an operating parameter of the internal combustion engine; Restore the previous value for the minimum valve stroke if the operating parameter is outside of a defined value range; otherwise retain the new value.