Abstract: In a method and a control apparatus for monitoring an exhaust gas probe, the exhaust gas probe is arranged in an exhaust gas channel. The exhaust gas channel is connected to an internal combustion engine, with the internal combustion engine being supplied with a rich or lean air/fuel ratio in an oscillating fashion. An amplitude of a signal based on the oscillating output signal of the exhaust gas probe is determined and used to evaluate the exhaust gas probe.

Abstract: In a method for correcting the output signal of a broadband lambda probe of an internal combustion engine, the influence of the air humidity on the lambda value determined by the broadband lambda probe is detected and is deducted by means of a compensation model. For this purpose, a measured air humidity is incorporated in the calibration of the broadband lambda probe during an overrun shut-off phase of the internal combustion engine.

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: 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: A regeneration method for a storage catalytic converter in an exhaust-gas purification system of an internal combustion engine, has the following steps: (a) switching of the internal combustion engine from a standard operating mode with a lean exhaust gas to a regeneration mode with a rich exhaust gas, (b) measurement of a nitrogen oxide concentration in the exhaust gas of the internal combustion engine after the switchover to the regeneration mode, (c) determination of a characteristic variable of a desorption peak of the measured nitrogen oxide concentration after the switchover to the regeneration mode, and (d) minimization of the characteristic variable of the desorption peak through controlling of the internal combustion engine as a function of the measured characteristic variable of the desorption peak.

Abstract: An internal combustion engine has a NOX storage catalyst. A storage capacity (NOX_STC) of the NOX storage catalyst is determined for the purpose of operating the internal combustion engine. The temperature (TEMP) of the NOX storage catalyst is increased if the storage capacity (NOX_STC) is less than a predefined threshold value.

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: The invention is distinguished by a method and a corresponding device for diagnosis of an individual catalytic converter of an exhaust gas purification unit assigned to an internal combustion engine in the Y configuration, despite the lack of exhaust gas probe between the individual catalytic converter and a main catalytic converter. The diagnosis proceeds on the basis of signals from the exhaust gas probes belonging to the exhaust gas purification unit. On the basis of these signals, the oxygen storage capacity of the individual catalytic converter is determined despite the lack of exhaust gas probe between the individual catalytic converter and the main catalytic converter.

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: 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: A plateau phase of a test signal of an exhaust gas probe located in a catalytic converter is detected following a jump from a preset rich air/fuel ratio in a combustion chamber of one cylinder to a preset lean air/fuel ratio, the plateau phase being obtained following the jump, and the duration is determined as a storage period. A plateau phase of the test signal, which is obtained following a jump from a preset lean air/fuel ratio to a preset rich air/fuel ratio, is detected following the jump, and the duration of the plateau phase is determined as an evacuation period. An allocation rule for assigning the test signal to a detected air/fuel ratio is adjusted according to the storage period and the evacuation period. To calibrate the exhaust gas probe, the allocation rule is adapted according to a plateau value of the test signal during the plateau phase.

Abstract: The desulfation of a NOx storage catalytic converter takes place in two phases. In a first phase, the NOx storage catalytic converter is alternately exposed to rich and lean exhaust gas. In a subsequent second phase, the NOx storage catalytic converter is operated using rich exhaust gas. This method permits the quantity of hydrogen sulfide that occurs during the desulfation process to be minimized and achieves at the same time an efficient removal of sulfate from the deep-seated layers of the NOx storage catalytic converter.

Abstract: To operate an internal combustion engine subvolumes of the fluid flowing into an intake duct in each instance during a predetermined time period are determined for each period. Tank purging values of a characteristic quantity are determined for each period. The characteristic quantity is representative of a tank purging fuel mass, which flowed through the tank purging valve in each instance during the predetermined time period. The successive subvolumes are added together, starting from the currently determined subvolume, to give a total subvolume, until the total subvolume is greater than or equal to an effective intake duct volume downstream of the tank purging valve.

Abstract: A device is designed for determining a pre-set air/fuel ratio in the combustion chamber of a cylinder of an internal combustion engine. The device is further designed for determining a filtered, pre-set air/fuel ratio in the combustion chamber of the cylinder by filtering the pre-set air/fuel ratio in the combustion chamber of the cylinder by means of a filter which models the dynamic behavior of the upstream region of the exhaust gas catalyst relative to the arrangement of the exhaust gas probe in the exhaust gas catalyst, in particular its storage, reduction and/or oxidation properties. The device is further designed for determining an adjustable variable by means of a regulator as a function of the filtered and pre-set air/fuel ratio, and of a sensed air/fuel ratio in the combustion chamber of the cylinder.

Abstract: The invention is distinguished by a method and a corresponding device for diagnosis of an individual catalytic converter of an exhaust gas purification unit assigned to an internal combustion engine in the Y configuration, despite the lack of exhaust gas probe between the individual catalytic converter and a main catalytic converter. The diagnosis proceeds on the basis of signals from the exhaust gas probes belonging to the exhaust gas purification unit. On the basis of these signals, the oxygen storage capacity of the individual catalytic converter is determined despite the lack of exhaust gas probe between the individual catalytic converter and the main catalytic converter.

Abstract: The invention relates to a method which is characterized in that before an active catalyst diagnosis is carried out the mixture is dynamically trimmed for all individual catalysts using a signal of a lambda sensor common to the individual catalysts. Once the mixture is successfully trimmed, the cylinder-based forced activation is adjusted in such a manner that the individual catalysts, by virtue of the charge imprinted thereon for a threshold catalyst, exceed their remaining oxygen storage capacity to such an extent that the lambda sensor is enabled to measure the storable charge. The cylinder-based lambda signals reconstructed from the sensor signal are then used to determine specific diagnostic values for every individual catalyst.

Abstract: Disclosed is an internal combustion engine comprising at least one cylinder and an exhaust manifold in which a catalytic converter, a first exhaust gas probe, and a second exhaust gas probe are disposed. The first exhaust probe is located upstream from the catalytic converter while the second exhaust gas probe is arranged downstream therefrom. A lambda Controller is provided which is configured so as to determine a lambda correction factor in accordance with a first test signal that is assigned to the first exhaust gas probe. A trim controller is provided to which a setpoint value and an actual value of a second test signal allocated to the second exhaust gas probe are fed as a control difference. The trim controller is configured so as to determine a proportionate corrective factor.

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: According to one embodiment of the inventive method, half the cylinders of an in-line cylinder arrangement or the entire internal combustion engine are forcibly excited cylinder-specifically in opposite direction to the other half of the cylinders in order to balance the cylinder-specific total torque. According to another embodiment of the invention, trim regulation which compensates differences between the air quantities and/or fuel quantities introduced into the individual cylinders with the aid of the signal of a joint lambda probe is done cylinder-specifically for the individual catalytic converters. The invention also relates to lambda regulation for the joint main catalytic converter mounted downstream of the cylinder-specific individual catalytic converters.

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.