Abstract: During a first driving cycle, a combustion process is controlled in at least one combustion chamber for the purpose of performing a check on an emission reduction system of an internal combustion engine. During a second driving cycle following the first cycle, a check is performed to establish whether an error in the emission reduction system was detected during the first cycle. An idle time between the first and the second cycles is determined, in the event of an error of the emission reduction system detected during the first cycle. During the second cycle, the combustion process in the at least one combustion chamber is only controlled for the purpose of the check on the emission reduction system, in the event of an error detected in the emission reduction system during the first cycle and in the event of the idle time being longer than a pre-determined repair time.

Abstract: In a method for operating an internal combustion engine with a crankcase breather venting into an intake tract, operating parameters of the internal combustion engine are measured 102. A mass flow of fuel from the crankcase into the intake tract is determined as a function of the operating parameters measured 103. The internal combustion engine is controlled 111 or monitored 108 as a function of the mass flow of fuel from the crankcase into the intake tract.

Abstract: An exhaust catalyst is charged with oxygen until saturated. A given first rich air/fuel ratio (LAM1_SP) is set in a combustion chamber of a cylinder. A first oxygen storage capacity value (OSC1) is determined depending on the measured signals (MS1, MS2) from first and second exhaust probes. The exhaust catalyst is charged with oxygen until saturated. A given second rich air/fuel ratio is set in the combustion chamber of the cylinder. A second oxygen storage capacity value (OSC2) is determined depending on the measured signal from the first and second exhaust probe. A corrected oxygen storage capacity value (OSC_COR) is determined depending on the first and second oxygen storage capacity values (OSC1, OSC2).

Abstract: An internal combustion engine has at least one cylinder, with which an injection valve for metering fuel is associated and an exhaust system with an exhaust gas catalytic converter. A first exhaust gas probe is disposed upstream of or in the exhaust gas catalytic converter, and a second exhaust gas probe is downstream. A lambda controller determines a regulating variable as a function of the first probe and a control variable acting on a fuel mass to be metered using the injection valve. A trim regulator determines a regulating variable thereof as a function of the second probe and the first trim control variable thereof as a function of a P regulator component and the second trim control variable thereof as a function of an I regulator component. A function of a predetermined evaluation of the first trim control variable decides whether the second trim control variable is adapted.

Abstract: In order to control an internal combustion engine, a fuel mass that is to be supplied to the respective cylinder is determined according to a load variable. An additional fuel mass to be measured once is determined, when the measuring signal of an oxygen probe arranged downstream from a three-way catalytic converter is characteristic of at least one pre-determined residual oxygen part, according to the course of the measuring signal. A once reduced fuel mass is determined, when the measuring signal is characteristic of at least one pre-determined residual fuel part, according to the course of the measuring signal. A corrected fuel mass to be measured is determined according to the fuel mass to be supplied and optionally less the once reduced fuel mass or the fuel mass to be measured once. An actuating signal for controlling the injection valve is generated according to the corrected fuel mass to be supplied.

Abstract: The invention relates to a method for determining the actual oxygen load of a 3-path catalyst of a lambda-controlled internal combustion engine, whereby a value for the actual oxygen load is calculated from the signal of a pre-catalyst lambda probe and the measured air mass flow rate by integration over time, whereby the post-catalyst lambda probe is initialized when the signal is interrupted.

Abstract: The invention relates to a method for regulating the lambda value of an internal combustion engine with a catalytic converter for subsequently treating the exhaust gases of the internal combustion engine, with a binary lambda probe, which is mounted upstream from the catalytic converter and which senses the composition of the exhaust gases. According to the invention, the lambda set value is superimposed with a lean/rich amplitude. This lean/rich amplitude has an integral component and a discontinuous component leading back to the lambda set value. When a change that differs from the change in the exhaust gas composition caused by the lean/rich amplitude is detected, the coefficient of the integral component is modified and/or a discontinuous component is added to the integral component or subtracted therefrom.

Abstract: An internal combustion engine with multiple cylinders and injection valves that are provided for the cylinders and that meter fuel also comprises an exhaust gas tract in which an exhaust gas catalytic converter is arranged. A characteristic value (OSC) of an oxygen storage capacity of the exhaust gas catalytic converter is determined. In accordance with the characteristic value (OSC), a heating measure (HM) for heating the exhaust gas catalytic converter is carried out.

Abstract: An exhaust catalyst is charged with oxygen until saturated. A given first rich air/fuel ratio is set in a combustion chamber of a cylinder. A first oxygen storage capacity value is determined depending on the measured signals from first and second exhaust probes. The exhaust catalyst is charged with oxygen until saturated. A given second rich air/fuel ratio is set in the combustion chamber of the cylinder. A second oxygen storage capacity value is determined depending on the measured signal from the first and second exhaust probe. A corrected oxygen storage capacity value is determined depending on the first and second oxygen storage capacity values.

Abstract: An internal combustion engine has an exhaust gas catalyst, a first exhaust gas sensor that is arranged for use in lambda control, and a second sensor that is arranged for trim control. The measuring signal of the second sensor is used to determine a NOx quality value depending on the HC quality value and the NOx correction factor. A lambda quality value is determined depending on an actual value and a basic set value of the air/fuel ratio. An error indicator is determined depending on the lambda quality value and the NOx quality value, the error indicator being representative of a mixture component error in a first range and being representative of an exhaust gas catalyst error in a second range. At least one control parameter of a trim control and/or the trim set value of the trim control is adapted depending on the NOx correction factor.

Abstract: Method and apparatus for operating an exhaust-gas catalytic converter (21) of an internal combustion engine having at least one cylinder (Z1-Z4) and one exhaust-gas section (4), in which the exhaust-gas catalytic converter (21) and a lambda probe (43) downstream of the exhaust-gas catalytic converter (21) are arranged. A characteristic value which is representative for the NOx concentration is determined as a function of a measured signal (VLS DOWN) of the lambda probe (43).

Abstract: A turbochargeable internal combustion engine contains a motor which has an exhaust manifold on the exhaust gas side, a turbocharger which has at least two turbocharger stages and, on the exhaust gas side, has an exhaust gas inlet and an exhaust gas outlet. The engine further has a primary catalytic converter, which is arranged on the exhaust gas side between the exhaust manifold of the engine block and the exhaust gas inlet of the turbocharger.

Abstract: An internal combustion engine has at least one cylinder and an exhaust gas tract, in which an exhaust gas sensor, that can be heated in a controlled manner, is arranged. An exhaust gas temperature of an exhaust gas flowing in the exhaust gas tract is determined as a function of the heating power (P_HEAT) supplied to the exhaust gas sensor. An estimated value of the exhaust gas temperature is determined as a function of a physical model of the combustion of the air/fuel mixture and of the exhaust gas tract as a function of at least one operating variable of the internal combustion engine, but independent of the heating power supplied to the exhaust gas sensor. Model parameters of the physical model are adapted as a function of a deviation of the estimated value and of the exhaust gas temperature determined by the supplied heating power.

Abstract: In the method for determining the alcohol concentration of the tank fuel after filling up with E85 fuel or E0 fuel, two corridors of possible lambda values for filling with E0 fuel and E85 are established according to the volumes of the tank fuel before and after filling, and the lambda values are taken into account in the evaluation.

Abstract: An internal combustion engine has an exhaust gas catalyst, a first exhaust gas sensor that is arranged in such a manner that it can be used in lambda control, and a second exhaust gas sensor that is arranged in such a manner that it can be used in trim control. A HC quality value (EFF_CAT_HC) which is representative of an oxygen storage capacity of the exhaust gas catalyst is determined depending on a measuring signal (VLS_DOWN) of the second exhaust gas sensor. A NOx correction factor (COR_NOX) is determined depending on the measuring signal (VLS_DOWN) of the second exhaust gas sensor, namely depending on signal portions that are representative of the residual oxygen. A NOx quality value (EFF_CAT_DIAL_NOX) is determined depending on the HC quality value (EFF_CAT_HC) and the NOx correction factor (COR_NOX).

Abstract: Method for lambda control in an internal combustion engine with a catalytic converter in an exhaust tract and at least one lambda probe mounted inside the catalytic converter. With this arrangement of the upstream probe there are signal delays which slow down the lambda control. To compensate, the measurement signals from the first lambda probe are applied to a lambda analysis unit which corrects measurement signal delays, and the corrected lambda probe signal is applied to a unit for lambda control. Both lambda probes are connected to a unit for lambda control.

Abstract: An exhaust-gas sensor signal (vls_down) of an exhaust-gas sensor that is disposed in an exhaust gas train downstream of at least one first catalytic converter volume (V1) and upstream of at least one second catalytic converter volume (V2) is acquired. An estimated value of an intermediate emission for a position of the exhaust-gas sensor is determined in dependence upon the exhaust-gas sensor signal (vls_down). An estimated value of an emission downstream of the at least one second catalytic converter volume (V2) is determined in dependence upon the estimated value of the intermediate emission and in dependence upon at least one predefined correction characteristic (fac_cor_ufc) or at least one predefined correction characteristics map for correcting the estimated value of the intermediate emission with regard to an influence of the at least one second catalytic converter volume (V2) upon the emission of the at least one exhaust gas component.

Abstract: A first exhaust gas sensor signal (vls_up) of a first exhaust gas sensor (AS1) is detected. In addition, a second exhaust gas sensor signal (vls_down) of a second exhaust gas sensor (AS2) is detected. A relevant first estimated value of an emission of at least one exhaust gas component is determined in relation to a position of the first exhaust gas sensor (AS1) in the exhaust gas tract as a function of the first exhaust gas sensor signal (vls_up) and a relevant second estimated value of an emission of the at least one exhaust gas component is determined in relation to a position of the second exhaust gas sensor (AS2) in the exhaust gas tract as a function of the second exhaust gas sensor signal (vls_down). A conversion rate (K) of the at least one exhaust gas component is estimated as a function of a ratio of the second estimated value and the first estimated value of the determined emission. The exhaust gas catalytic converter is diagnosed as a function of the determined conversion rate (K).

Abstract: For operating a internal combustion engine a first characteristic value is determined depending on a distance integral of at least a portion of a control signal of an oxygen sensor control based on control reference signal characteristics across a given time period. Depending on the first characteristic value (KW—1) a quality value (GW—1) is determined. Depending on the quality value (GW1) either the existence or the non existence of an error of the exhaust sensor is detected.

Abstract: An internal combustion engine has an exhaust gas catalyst, a first exhaust gas sensor that is arranged for use in lambda control, and a second sensor that is arranged for trim control. The measuring signal of the second sensor is used to determine a NOx quality value depending on the HC quality value and the NOx correction factor. A lambda quality value is determined depending on an actual value and a basic set value of the air/fuel ratio. An error indicator is determined depending on the lambda quality value and the NOx quality value, the error indicator being representative of a mixture component error in a first range and being representative of an exhaust gas catalyst error in a second range. At least one control parameter of a trim control and/or the trim set value of the trim control is adapted depending on the NOx correction factor.