Abstract: Method for diagnosing at least one exhaust gas sensor (22;24;26) of an internal combustion engine (10) disposed in an exhaust duct (21), where ambient air (12) is actively introduced into the exhaust duct (21) by means of a device (27), when an operating state is present in which the internal combustion engine (10) does not produce an exhaust gas mass flow, and the diagnosis of the at least one exhaust gas sensor (22;24;26) disposed in the exhaust duct (21) is subsequently carried out.

Abstract: The invention relates to a method (200) for operating an internal combustion engine (110), comprising providing and combusting an air-fuel mixture of a first composition, determining (210) a current composition of a combustion exhaust gas produced during the combustion, determining (220) an emission collective, which comprises a total amount emitted over a predefined interval for at least one component of the combustion exhaust gas, from multiple successively determined current compositions of the combustion exhaust gas, and setting (250) a second composition of the air-fuel mixture depending on the emission collective determined. The invention also relates to a computing unit and a computer program product for carrying out such a method.

Abstract: A method (100) is proposed for operating an internal combustion engine (210), which comprises a lean-burn engine having compression-ignition, having a throttle valve (213) in an air path (212) upstream of the internal combustion engine (210) and an exhaust gas posttreatment system (202) downstream of the internal combustion engine (210), comprising a control of the internal combustion engine (210) according to a present load demand (130) using metering of an amount of fuel in dependence on the present load demand; and if a load demand (130) is absent in a heating operating mode, further comprising partially closing (140) the throttle valve (213) and defining a minimum value for the amount of fuel, which is greater than zero. Furthermore, a computing unit and a computer program for carrying out such a method (100) are proposed.

Abstract: A method for diagnosing an exhaust component in an exhaust passage for an internal combustion engine of a vehicle. In the method, operating parameters of the internal combustion engine are monitored and recorded by a control unit while the internal combustion engine is running. If a predefined emission threshold for the exhaust component for compliance with emissions is found to have been exceeded, the current operating parameters of the internal combustion engine are stored in a control unit. The operating state of the internal combustion engine when the predefined emission threshold is exceeded is reproduced on a vehicle test bench using the stored operating parameters. The diagnosis of the exhaust component is carried out based on a comparison between the current measured value from the exhaust component and the current measured value from an emission measuring device and/or the predefined emission threshold.

Abstract: Determining a functionality of an exhaust gas sensor in an exhaust gas system having a catalytic converter and a first exhaust gas sensor upstream of the catalytic converter and a second exhaust gas sensor downstream of the catalytic converter. The first and the second exhaust gas sensors are heated to a temperature above a minimum operating temperature.; A first sensor signal of the first exhaust gas sensor; and a second sensor signal of the second exhaust gas sensor are determined.

Abstract: Method for diagnosing at least one exhaust gas sensor (22;24;26) of an internal combustion engine (10) disposed in an exhaust duct (21), where ambient air (12) is actively introduced into the exhaust duct (21) by means of a device (27), when an operating state is present in which the internal combustion engine (10) does not produce an exhaust gas mass flow, and the diagnosis of the at least one exhaust gas sensor (22;24;26) disposed in the exhaust duct (21) is subsequently carried out.

Abstract: A method (200) for ascertaining a catalytic converter state is proposed, wherein an exhaust-gas catalytic converter (130) is monitored on the basis of a catalytic converter model. Here, the catalytic converter model is adapted (250) in a manner dependent on measured values detected by means of one or more sensors (145, 147), wherein a frequency and/or a degree of the adaptation of the catalytic converter model is detected (260). The catalytic converter state is ascertained (270) as non-critical if the frequency and/or the degree of the adaptation do not exceed a predeterminable threshold value or is ascertained (270) as critical if the frequency and/or the degree of the adaptation exceed the predeterminable threshold value.

Abstract: A method (100) is proposed for operating an internal combustion engine (210), which comprises a lean-burn engine having compression-ignition, having a throttle valve (213) in an air path (212) upstream of the internal combustion engine (210) and an exhaust gas posttreatment system (202) downstream of the internal combustion engine (210), comprising a control of the internal combustion engine (210) according to a present load demand (130) using metering of an amount of fuel in dependence on the present load demand; and if a load demand (130) is absent in a heating operating mode, further comprising partially closing (140) the throttle valve (213) and defining a minimum value for the amount of fuel, which is greater than zero. Furthermore, a computing unit and a computer program for carrying out such a method (100) are proposed.

Abstract: A method for diagnosing a plurality of lambda sensors which are arranged upstream of an exhaust gas catalytic converter in a plurality of exhaust gas banks of a multi-flow exhaust gas system of an internal combustion engine. An opposite lambda offset of the lambda sensors is identified (54) when a difference (?T) between a measured exhaust gas temperature (Tmeasure) and a modeled exhaust gas temperature (Tmod) downstream of the exhaust gas catalytic converter overshoots a threshold value (S).

Abstract: A method for operating an engine system that includes an internal combustion engine and an exhaust aftertreatment device. The method includes: carrying out a filling control in order to regulate a filling level of the exhaust aftertreatment device as a function of a predefined filling level setpoint value, a lambda setpoint value for a lambda regulation being predefined as a manipulated variable, adapting the filling control with the aid of an adaptation variable that indicates a correction value for the lambda setpoint value, and storing an adaptation value as a function of an operating range of the engine system, the adaptation value in question being updated with the value of the adaptation variable for the instantaneous operating range.

Abstract: A method for operating an exhaust-gas burner (B) of a vehicle (100) which has at least an internal combustion engine (V) and a catalytic converter (C1, C2), wherein exhaust gases (22, 24) of the exhaust-gas burner (B) are merged, upstream of the catalytic converter (C1, C2), with exhaust gases (12) of the internal combustion engine (V), forming an exhaust-gas mixture, wherein a lambda value of the exhaust gases (22, 24) of the exhaust-gas burner (B) is set in a manner dependent on a lambda value of the exhaust gases (12) of the internal combustion engine (V).

Abstract: A method (200) for ascertaining a catalytic converter state is proposed, wherein an exhaust-gas catalytic converter (130) is monitored on the basis of a catalytic converter model. Here, the catalytic converter model is adapted (250) in a manner dependent on measured values detected by means of one or more sensors (145, 147), wherein a frequency and/or a degree of the adaptation of the catalytic converter model is detected (260). The catalytic converter state is ascertained (270) as non-critical if the frequency and/or the degree of the adaptation do not exceed a predeterminable threshold value or is ascertained (270) as critical if the frequency and/or the degree of the adaptation exceed the predeterminable threshold value.

Abstract: A method for operating an exhaust-gas burner (B) of a vehicle (100) which has at least an internal combustion engine (V) and a catalytic converter (C1, C2), wherein exhaust gases (22, 24) of the exhaust-gas burner (B) are merged, upstream of the catalytic converter (C1, C2), with exhaust gases (12) of the internal combustion engine (V), forming an exhaust-gas mixture, wherein a lambda value of the exhaust gases (22, 24) of the exhaust-gas burner (B) is set in a manner dependent on a lambda value of the exhaust gases (12) of the internal combustion engine (V).

Abstract: A method for diagnosing a plurality of lambda sensors which are arranged upstream of an exhaust gas catalytic converter in a plurality of exhaust gas banks of a multi-flow exhaust gas system of an internal combustion engine. An opposite lambda offset of the lambda sensors is identified (54) when a difference (?T) between a measured exhaust gas temperature (Tmeasure) and a modeled exhaust gas temperature (Tmod) downstream of the exhaust gas catalytic converter overshoots a threshold value (S).

Abstract: A method for operating an engine system that includes an internal combustion engine and an exhaust aftertreatment device. The method includes: carrying out a filling control in order to regulate a filling level of the exhaust aftertreatment device as a function of a predefined filling level setpoint value, a lambda setpoint value for a lambda regulation being predefined as a manipulated variable, adapting the filling control with the aid of an adaptation variable that indicates a correction value for the lambda setpoint value, and storing an adaptation value as a function of an operating range of the engine system, the adaptation value in question being updated with the value of the adaptation variable for the instantaneous operating range.