A system for diagnosing engine braking performance of an engine comprising a plurality of cylinders comprises an exhaust manifold pressure sensor configured to detect an exhaust manifold pressure corresponding to exhaust gas emitted from a plurality of cylinders. A controller is configured to determine an exhaust manifold pressure value corresponding to at least one cylinder of the plurality of cylinders that is being used for engine braking, from an exhaust manifold pressure sensor signal received from the exhaust manifold pressure sensor. The controller is also configured to determine an engine braking value based on the exhaust manifold pressure value.

An emission control device for an internal combustion engine is configured to perform a particulate matter trap function of trapping, with a particulate filter, particulate matter contained in exhaust gas which flows in an exhaust passage of the internal combustion engine. The emission control device includes a controller. The controller is configured to calculate a particulate matter accumulation amount, which is a total amount of particulate matter trapped by the particulate filter based on an operation condition of the internal combustion engine. The controller is configured to stop calculating the particulate matter accumulation amount when the particulate matter trap function is not functioning.

The disclosure relates to a method for determining the icing condition of a component of the exhaust-gas system of a motor vehicle that is not arranged directly in the exhaust-gas mass flow and/or of the feed line of the component. The method includes: determining a water quantity actually present in the component and in the feed line thereof and the state of aggregation of the water quantity; determining an energy quantity required for deicing and for volatilizing the water quantity; and determining an energy quantity supplied for deicing and for volatilizing the water quantity by radiated heat from components arranged directly in the exhaust-gas mass flow of the exhaust-gas system of the motor vehicle to the surroundings. The method also includes determining the icing condition of the component by comparing the energy quantity supplied for deicing and for volatilization with the energy quantity required for deicing and for volatilization.

An automotive exhaust aftertreatment system for reducing effluents, such as nitrous oxides (NOx), in exhaust gasses passing through the system. The automotive exhaust aftertreatment system includes a dosing unit configured to inject primary and secondary reductant fluids into exhaust gasses based on various strategies to optimize operation of the system.

A heater system for an exhaust system is provided. The heater system includes a heater disposed in an exhaust conduit. The heater includes a plurality of heating elements disposed in the exhaust conduit. A heating control module controls the plurality of heating elements differently according to operating conditions specific to each heating element. In other forms, the heater system for an exhaust system has a plurality of heating zones, instead of a plurality of heating elements. The heating control module controls the plurality of heating zones differently according to operating conditions specific to each heating zone.

Methods and systems for diagnosing operation of an exhaust gas recirculation system of an internal combustion engine are described. In one example, the EGR system is diagnosed while an engine that includes the EGR system is not rotating and combusting fuel. The EGR system is diagnosed when the engine is not operating so that vehicle passengers are not disturbed by the diagnostic and so that flow estimates through the EGR system may not be disturbed by pressure changes that may be related to combustion within the engine.

A method is described for monitoring an exhaust aftertreatment system of a combustion engine, with a pressure difference sensor that captures a first pressure difference between a first sampling point and a second sampling point. A second pressure difference between the second sampling point and the environment is captured. A defect is detected based on the second pressure difference.

The invention relates to a method for determining a loading of a soot filter with soot particles from an exhaust gas mass flow of an internal combustion engine in a motor vehicle, a control device for an internal combustion engine having a soot filter, and a computer program product for carrying out the method. In the first step 100 of the method a characteristic curve for the relationship between the exhaust gas mass flow, exhaust gas temperature, ambient pressure, and pressure drop across the soot filter without loading is determined; in the second step 200 a second exhaust gas mass flow and a second pressure drop that occurs during loading of the soot filter are determined; in the third step 300, from the characteristic curve the first pressure drop is determined for which the first and second exhaust gas mass flows have the same value; in the fourth step 400 an estimated value for the loading of the soot filter is computed via a real-time parameter estimation, preferably by use of the gradient method, based on the previously determined parameters. The method allows a reliable determination of the instantaneous loading of a particulate filter, regardless of the type of measuring signals used in each case for characterizing the loading behavior of the soot filter.

A diagnostic engine calibration module is provided that is structured to diagnose a vehicle system by causing the vehicle system to operate outside of one or more calibration parameters. The diagnostic engine calibration module includes a diesel particulate filter (DPF) pressure module structured to determine a pressure differential across a DPF of an engine of the vehicle system and compare the determined pressure differential against a plurality of predetermined fault thresholds to diagnose the DPF, the plurality of predetermined fault thresholds including a predetermined minimum pressure threshold and a predetermined maximum pressure threshold.

A system for determining accumulation of Silicone dioxide (SiO.sub.2) in an aftertreatment system of an engine includes a pressure sensor arrangement having at least one pressure sensor therein. The pressure sensor is fluidly coupled to an exhaust pipe associated with the aftertreatment system. A controller is disposed in communication with the pressure sensor. The controller is configured to monitor back pressure of the aftertreatment system from at least one signal output by the pressure sensor arrangement and determine a level of accumulation of SiO.sub.2 in the aftertreatment system based on the monitored back pressure of the aftertreatment system. Based on the determination of the level of accumulation of SiO.sub.2 in the aftertreatment system by the controller, the controller outputs a signal to a notification device for facilitating the notification device to notify an operator of the level of accumulation of SiO.sub.2 in the aftertreatment system.