The invention relates to a method for automatically detecting clogging of a sensor pipe extending between a pressure sensor and an exhaust manifold of an internal combustion engine, wherein the pressure sensor enables to record a signal representative of the relative pressure over time. The method includes at least one of the following steps: a) determining, while the engine runs in a steady operation state, an average amplitude of oscillations of the signal over a first period of time, the sensor pipe being considered clogged when said average amplitude is lower than a first threshold; b) monitoring, from the time the engine has been turned off, the signal over a second period of time, the sensor pipe being considered clogged when the integral of the signal is greater than a second threshold.

A method for operating an exhaust gas burner (3) downstream of an internal combustion engine (1) and upstream of an exhaust gas catalytic converter (4), comprising controlling an ignition device (12) of the exhaust gas burner (3) during a predeterminable preheating phase without supplying fuel (11) to the exhaust gas burner (3) during the preheating phase and, after completion of the preheating phase, supplying fuel (11) to the exhaust gas burner (3) and burning the supplied fuel (11) in the exhaust gas burner (3). A processor unit and a computer program product for carrying out such a method are furthermore proposed.

A method for detecting a replacement of a differential pressure sensor arranged for measuring a differential pressure across a filter of an aftertreatment system of a vehicle. The method includes determining a sensor offset value being an offset from a sensor value measured with a differential pressure sensor; adding an adaption value to the measured sensor value to compensate for the offset value to centre the sensor value around a predetermined level; if a sum of a subsequently measured sensor value and the adaption value exceeds a limit value, concluding that the differential pressure sensor has been replaced.

Disclosed are methods and systems for monitoring a diesel generator system that includes a DPF filter in order to provide a highly efficient approach for monitoring the status of a DPF filter in order to determine if a regeneration is required. The methods and systems not only permit the ongoing determination of when a regeneration is appropriate in order to prevent excessive engine backpressure, but also accomplish this objective in a manner that reduces fuel consumption over the course of engine use.

A method for detecting a replacement of a differential pressure sensor arranged for measuring a differential pressure across a filter of an aftertreatment system of a vehicle. The method includes determining a sensor offset value being an offset from a sensor value measured with a differential pressure sensor; adding an adaption value to the measured sensor value to compensate for the offset value to centre the sensor value around a predetermined level; if a sum of a subsequently measured sensor value and the adaption value exceeds a limit value, concluding that the differential pressure sensor has been replaced.

A method for heating a first exhaust gas purification device and a second exhaust gas purification device of an exhaust system of an internal combustion engine of a motor vehicle, has the following steps: determining a first actual temperature of the first device and a second actual temperature of the second device, determining a first setpoint temperature of the first device and a second setpoint temperature of the second device by means of a heating coordination device, determining a first heat demand of the first device and a second heat demand of the second device, creating a heating specification for the first device and for the second device, relaying the heating specification to an engine control device of the motor vehicle, and controlling the internal combustion engine by means of the engine control device as a function of the heating specification.

Provided is a muffler valve 1 that opens and closes an exhaust passage according to a pressure of an exhaust gas of an engine. A valve body 3 is swingably supported by a support shaft 4 with respect to a valve seat 2 having an opening 22, the valve body 3 is urged in a closing direction by a coil spring 5 externally inserted on the support shaft 4, a valve seat hook portion 23 is provided so as to embrace both ends of the support shaft 4 in a circumferential direction and is fixed to the support shaft 4, and a valve body winding portion 34 is provided so as to embrace the coil spring 5 in the circumferential direction from a direction opposite to the valve seat hook portion 23 and embrace the coil spring 5 over an entire length of the coil spring 5 in the circumferential direction. It is possible to prevent or suppress axial misalignment of the coil spring coaxially externally inserted on the support shaft for opening and closing the valve body as much as possible, and appropriately control the opening and closing of the valve body with high stability.

A method is provided for ascertaining a NO.sub.x concentration and an NH.sub.3 slip downstream from an SCR catalytic converter of an internal combustion engine of a vehicle. State variables of an internal combustion engine as first input variables and an updated NH.sub.3 fill level of the SCR catalytic converter as a second input variable cooperate with at least one machine learning algorithm or at least one stochastic model. The at least one machine learning algorithm or at least one stochastic model calculates the NO.sub.x concentration and the NH.sub.3 slip downstream from the SCR catalytic converter as a function of the first input variables and the second input variables and output the same as output variables.

An exhaust gas system for a motor vehicle includes an exhaust gas burner and a pressure sensor for sensing flame formation in the exhaust gas burner.

The present disclosure relates to internal combustion engines. The teachings thereof may include monitoring a secondary air system with which secondary air is introduced into exhaust of the internal combustion engine wherein individual cylinders of the internal combustion engine are associated with one of at least two cylinder banks and a separate exhaust duct is associated with each cylinder bank. The methods may include delivering secondary air with a compression arrangement via a common secondary air line divided into a number of individual secondary air sublines corresponding to the number of exhaust ducts at a branching point downstream of the compression arrangement; controlling the secondary air to simultaneously enable or inhibit the flow to the individual secondary air sublines; detecting values for the pressure downstream of the compression arrangement and upstream of the branching point; detecting pulsations of a pressure in each cylinder bank when the compression arrangement is activated and the throughflow control arrangement set into the open state; summing the pulsations; comparing each of summed-up values with threshold values; and if the respective threshold value is exceeded, identifying a fault in the throughflow control arrangement.