Abstract: An exhaust emission control device includes a first detection unit for detecting a NOx adsorption amount and an oxygen storage amount of a three-way catalyst and a NOx purification catalyst during rich spike, a second detection unit for detecting the oxygen storage amount of the three-way catalyst and the NOx purification catalyst until the output of a second air-fuel sensor becomes lean after the rich spike, and a deterioration determination unit for determining deterioration of the NOx purification catalyst based on a detected value of the first detection unit and that of the second detection unit.

Abstract: There are provided calculating a differential pressure deposition amount of PM deposited in a DPF based on an exhaust gas flow rate and a differential pressure of the DPF, calculating a model deposition amount of the PM using a model in which a PM amount burned in the DPF is subtracted from the PM amount, calculating a time change rate of the differential pressure deposition amount, and setting a first coefficient to be larger than a second coefficient when the exhaust gas flow rate exceeds a predetermined value and setting the first coefficient to be small when the exhaust gas flow rate exceeds the predetermined value and the time change rate is a predetermined threshold or more when multiplying the differential pressure deposition amount and the model deposition amount by the first and second coefficients, respectively, and calculating an addition value of the respective multiplied values as the PM deposition amount.

Abstract: A method is provided for monitoring an emission device coupled to an engine. In one example approach, the method comprises: following a deceleration fuel shut-off duration, indicating degradation of the emission device based on an amount of rich products required to cause a sensor to become richer than a threshold. The amount of rich products required may be correlated to an amount of oxygen stored in the emission device. The indication of emission device degradation may be further based on air mass and temperature during delivery of the required rich products.

Abstract: According to one embodiment, a sensor module includes a sensor probe that has at least two arms coupled together at a central location with each of the at least two arms extending radially outwardly away from the central location. Each of the at least two arms includes one of a plurality of openings and an elongate opening extending radially along the arm. The at least two arms define fluid flow channels therein. The sensor module also includes at least one extractor coupled to the probe. The at least one extractor includes a fluid flow channel that is communicable in fluid receiving communication with fluid flowing through the fluid flow channel of at least one of the at least two arms. Further, the sensor module includes at least one sensor that is communicable in fluid sensing communication with fluid flowing through the at least one extractor.

Abstract: An emission control system for an engine includes a catalyst and an exhaust-gas sensor provided downstream of the catalyst in a flow direction of exhaust gas. The exhaust-gas sensor includes a sensor element that includes a pair of electrodes and a solid electrolyte body located between the electrodes. The emission control system further includes a constant current supply portion that changes an output characteristic of the exhaust-gas sensor by applying a constant current between the electrodes, a catalytic-state determination portion which determines a rich/lean state of the catalyst, a rich direction control portion which performs and terminates a rich direction control depending on the rich/lean state of the catalyst, a lean direction control portion which performs a lean direction control after the rich direction control, and a characteristic control portion which performs a lean responsiveness control at least during the lean direction control.

Abstract: A catalyst degradation detection method for use with a zero ceria catalyst. The method uses techniques to measure transient responses to engine control events of upstream and downstream sensors to determine catalyst degradation and performance. By measuring transient behavior, the method can determine catalyst degradation and performance based on the limited oxygen storage of precious metal catalysts that do not include added ceria or other materials with high oxygen capture rates.

Abstract: A diagnostic method is provided for a particle filter arranged in exhaust-gas flow of an internal combustion engine. A particle concentration is detected by a particle sensor positioned downstream of the particle filter. The combustion-relevant engine parameters are briefly changed by an engine controller in such a way that an untreated emissions concentration from the engine is significantly increased. A filter fault message is output if the detected associated measurement values of the particle concentration exceed a detection threshold value of the particle sensor, which is in particular considerably greater than a predefined, preferably volume-related particle limit value.

Abstract: Various systems and methods are described for a particulate matter sensor coupled to an exhaust system of an engine. One example method comprises, during a measurement mode, generating a particulate flow rate based on the sensor and adjusting one or more engine operating parameters based on the flow rate. The method further includes, during a reduced contamination mode, heating the sensor to repel particulate from the sensor, and not adjusting the one or more operating parameters based on the sensor.

Abstract: A system and method for initiating an engine after-run state and controlling a nitrogen oxide sensor self-diagnostic tool are provided. The system may include an internal combustion engine, an exhaust system, a selective catalytic reduction (SCR) device and at least two NOx sensors to measure the efficiency of the SCR device and a controller or host machine. The controller, via the present method, executes a first control action to disable the self-diagnostic tool when one of an occurrence of a particulate filter regeneration event and a non-occurrence of a calibration threshold is detected. The controller executes a second control action, initiating an engine after-run state and enabling the self-diagnostic tool when one of a non-occurrence of a particulate filter regeneration event and an occurrence of the calibration threshold is detected.

Abstract: Described herein are various embodiments of an apparatus, a system, and a methods for reducing NOx emissions using ammonia storage on an SCR catalyst. For example, according to one embodiment, an apparatus for controlling an SCR system of an internal combustion engine system includes an ammonia storage module and a reductant dosing module. The ammonia storage module determines an ammonia storage surface coverage on an SCR catalyst of the SCR system and an ammonia compensation value based on one of an excess ammonia flow rate entering the SCR catalyst and an excess NOx flow rate entering the SCR catalyst. The reductant dosing module that generates a reductant dosing command based on the ammonia compensation value.

Abstract: A control apparatus (100) for a gas sensor (10) which includes a cell (2) composed of a solid electrolyte body and a pair of electrodes provided thereon. The control apparatus includes voltage application means (70) for applying a single pulse voltage to the cell over a constant energization time T; first-output-value obtaining means 70 for obtaining a first output value Vri1 from the cell when a first time t1 shorter than the constant energization time has elapsed; second-output-value obtaining means (70) for obtaining a second output value Vri2 from the cell when a second time t2 shorter than the constant energization time but longer than the first time has elapsed; and deterioration-degree detection means 70 for detecting the degree of deterioration of the cell on the basis of a difference ?Vri between the second output value and the first output value.

Abstract: A method for predicting sulfur oxides (SOx) stored at a denitrification (DeNOx) catalyst may include calculations of the mass flow of SOx poisoned at the DeNOx catalyst, the mass flow of SOx released from the DeNOx catalyst, and the SOx amount poisoned at the DeNOx catalyst by integrating the value obtained by subtracting the released mass flow of SOx from the poisoned mass flow of SOx. An exhaust system using the method may comprise an engine having a first injector, an exhaust pipe, a second injector mounted at the exhaust pipe and injecting a reducing agent, a DeNOx catalyst mounted at the exhaust pipe and reducing SOx or nitrogen oxides (NOx) or both contained in the exhaust gas by using the reducing agent, and a control portion electrically connected to the system and performing the calculations and controls.

Abstract: In one exemplary embodiment of the invention, a method for controlling regeneration for an exhaust system including a particulate filter is provided, where the method includes determining a mass flow rate of oxygen, determining a particulate mass, providing information describing desired set point temperatures corresponding to oxygen mass flow rates and particulate mass values and determining a temperature set point for exhaust gas entering the particulate filter based on the mass flow rate of oxygen, the particulate mass and the information describing desired set point temperatures corresponding to oxygen mass flow rates and particulate mass values. The method further includes communicating a signal to control a parameter for at least one selected from the group consisting of: a hydrocarbon injector, a heating device and a fuel injector configured to provide hydrocarbon post-injection to a cylinder of the internal combustion engine, the controlling based on the determined temperature set point.

Abstract: In one exemplary embodiment of the invention, a method for controlling regeneration for an exhaust system of an internal combustion engine, wherein the exhaust system includes a particulate filter is provided, where the method includes determining a mass flow rate of oxygen received from the internal combustion engine, determining a particulate mass within the particulate filter, determining a desired particulate burn rate based on the mass flow rate of oxygen and the particulate mass and determining a current particulate burn rate. The method also includes determining a correction value based on the desired particulate burn rate and the current particulate burn rate, determining a temperature set point for exhaust gas entering the particulate filter based on the correction value, an engine speed and an engine load and communicating a signal, from a controller, to control a parameter for a regeneration system based on the determined temperature set point.

Abstract: A device and a method for producing electrical energy from an exhaust gas of an internal combustion engine include a generator with an exhaust gas inlet, an exhaust gas outlet and a heat exchange portion therebetween. The heat exchange portion includes a plurality of flow paths for the exhaust gas. The flow paths are at least partially surrounded by thermoelectric elements which are in thermally conductive communication with a cooling device on a side facing away from the flow path. A motor vehicle having the device or carrying out the method, is also provided.

Abstract: An exhaust system (10) for a dual fuel engine, which engine is adapted to operate in a first mode in which the engine is fuelled entirely by a liquid fuel, and a second mode in which the engine is fuelled predominately by a gaseous fuel, the system comprising a first oxidation catalyst (22), a first temperature sensor (30) adapted to measure a core temperature of the first oxidation catalyst, and a controller (32) for controlling whether the engine operates in the first mode or the second mode, wherein the first temperature sensor is operatively connectable to the controller such that the controller prevents the engine from running in the second mode if the core temperature of the first oxidation catalyst is below a predetermined temperature.

Abstract: An engine control system for a working machine measures the sulfur content of an exhaust gas since sulfur is detrimental to normal functioning of an exhaust gas aftertreatment device. Each time a key switch is turned ON to start an engine, the engine control system compares a remaining fuel amount memorized at the last stop of the engine and a remaining fuel amount detected at the current start of the engine. The engine control system performs a sulfur concentration measurement process only when the remaining fuel amount is increased. A target revolution speed Na appropriate for measuring the concentration of sulfur is set and when the temperature of the exhaust gas is within a predetermined temperature range and a target time has elapsed, the engine control system determines whether the sulfur concentration exceeds a threshold value. If the sulfur concentration exceeds the threshold value, an alarm display device is activated.

Abstract: A system for improving operation of an engine having a particulate matter sensor is presented. The system may be used to improve engine operation during cold starts especially under conditions where water vapor or entrained water droplets are present in vehicle exhaust gases. In one embodiment, an engine controller that activates a heater of an exhaust gas sensor after an output of a particulate matter sensor exceeds a threshold value after an engine is started.

Abstract: In an internal combustion engine, inside of an engine exhaust passage, air-fuel ratio sensors each of which has a solid electrolyte, electrodes which respectively cover the two side surfaces of the solid electrolyte, and a diffusion resistance layer which covers one of electrodes are arranged. In operation, the greater the amounts of deposition of sulfur ingredients at the air-fuel ratio sensors, the smaller the amounts of change of the air-fuel ratios detected by the air-fuel ratio sensor and the longer the time period of change of the air-fuel ratios. The amounts of sulfur poisoning of the air-fuel ratio sensors are detected from the changes of the air-fuel ratios detected by the air-fuel ratio sensors.

Abstract: A vehicle includes an engine having an exhaust port, an exhaust system for conditioning an engine exhaust stream, a nitrogen oxide (NOx) sensor positioned within the exhaust stream, and a controller. The controller has an out-of-range diagnostic tool for evaluating a range performance of the sensor. The controller detects a predetermined engine-on fuel shutoff event, and then temporarily disables the diagnostic tool during the fuel shutoff event. The fuel shutoff event may be a vehicle deceleration-based event. A selective catalytic reduction (SCR) device may be positioned within the exhaust system, with at least one NOx sensor positioned at the outlet of the SCR device. An additional NOx sensor may be positioned in proximity to the exhaust port. A method for use aboard the above vehicle includes detecting the engine-on fuel shutoff event via the controller, and temporarily disabling the diagnostic tool for the duration of the detected fuel shutoff event.

Abstract: A gas sensor control apparatus is provided which controls an operation of a gas sensor made up of a solid electrolyte body and a pair of electrodes to output a signal indicating the concentration of a given gas component contained in gas. The gas sensor control apparatus includes a constant current circuit that is connected electrically to one of the electrodes of the gas sensor and supplies a constant current thereto and a controller. The controller supplies a constant current to the gas sensor so that it flows from one of the electrodes to the other in a selected direction, thereby changing a response time the gas sensor takes to react to a change in concentration of the gas component. This results in an increased accuracy, for example, in controlling an air-fuel ratio of a mixture to an internal combustion engine in an engine control system.

Abstract: Various systems and methods are described for detecting ammonia slip. In one example method, an amount of exhaust gas recirculation is reduced when output from an exhaust gas sensor indicates an increase in nitrogen oxide above a threshold amount. When the sensor output increases above a second threshold while the exhaust gas recirculation is reduced, the sensor output is allocated to nitrogen oxide; and when the sensor output does not increase above a second threshold while the exhaust gas recirculation is reduced, the sensor output is allocated to ammonia.

Abstract: A marine engine exhaust system has an exhaust conduit conveying engine exhaust gas from upstream to downstream, a sensor sensing oxygen content of the exhaust gas in the conduit, and a shield located in the conduit. The shield is configured to shield the sensor from deleterious effects of liquid when liquid and exhaust gas is reverted in the exhaust conduit from downstream to upstream.

Abstract: The adherence to future legally obligatory exhaust gas limit values for diesel vehicles in Europe, North America and Japan requires not only the removal of particles but also effective removal of nitrogen oxides from the exhaust gas (‘deNOx’). The ‘active SCR process’ is the preferred method for this. The nitrogen oxide conversions achieved by means of this process are particularly high when an optimal NO2/NOx ratio, preferably 0.5, is set upstream of the SCR catalyst. The invention proposes a process which solves the problem of supplying NO2 in accordance with requirements by means of temperature control of the precatalyst which is decoupled from the operating state of the engine.

Abstract: A heater control device of an oxygen concentration sensor is provided in which even in a case where an internal combustion engine is automatically stopped by idle stop control after cold start-up, it is possible to start energization of a heater at an appropriate time.

Abstract: A method for regenerating an open particle separator includes at least determining at least one parameter, as a characteristic variable of a regeneration capability of the open particle separator. The at least one parameter is compared with a first threshold value. At least one portion of a comparison period during which the parameter has reached the first threshold value is determined. The portion is compared with a first minimum portion corresponding to a minimum regeneration time in the comparison time period. Measures are initiated to influence the parameter so that the parameter lies at least according to the first minimum portion and the first threshold value is reached and/or the open particle separator is regenerated. A motor vehicle having at least one open particle separator is also provided.

Abstract: A gas additive and a liquid additive are supplied efficiently. There are provided a liquid supply device that stores a liquid additive and supplies the liquid additive into an exhaust passage of an internal combustion engine, a gas supply device that stores a gas additive and supplies the gas additive into the exhaust passage, a catalyst that is arranged in the exhaust passage at a downstream side of locations at which the additives are supplied from the liquid supply device and the gas supply device, respectively, with the additives reacting in the catalyst, and an adjustment device that adjusts an amount of the liquid additive to be added from the liquid supply device and an amount of the gas additive to be added by the gas supply device in accordance with a rule defined beforehand.

Abstract: An exhaust purification system is provided that can decrease the load acting on a device treating PM, even when switched to stoich operation. The exhaust purification system includes: a PM treatment device, a three-way purification catalyst, an LAF sensor, and an ECU (3) that performs feedback control so that an LAF sensor output (Vex) becomes a target value (Vop) determined so that the three-way purification reaction is optimized during stoich operation. The ECU (3) includes a fuel controller (32) that determines a fuel injection amount (Gfuel) so that a state in which an air/fuel ratio of the air/fuel mixture is leaner than stoich and a state richer than stoich are alternately realized by modulating a fuel correction amount (dGfuel) determined so as to cause the LAF sensor output (Vex) to converge to the target value (Vop) by employing a predetermined modulation algorithm.

Abstract: An exhaust treatment system is disclosed that can diagnose the performance of an exhaust treatment oxidation catalyst in converting NO to NO2. The exhaust treatment system is fluidly coupled to an internal combustion engine, and includes an oxidation catalyst disposed in an engine exhaust stream; a reductant source for injecting a reductant into the exhaust stream downstream of the oxidation catalyst; an SCR catalyst disposed in the exhaust stream downstream of the reductant source; and a gas sensor, disposed in the exhaust stream downstream of the oxidation catalyst and upstream of the reductant source, comprising a plurality of sensing or pumping cells that measures NO concentration in the exhaust gas and NO2 concentration in the exhaust gas.

Abstract: An exhaust treatment system includes a nitrogen oxide (NOx) monitoring module and a regeneration control module. The NOx monitoring module monitors first and second NOx levels in an exhaust stream produced by an engine, wherein the first NOx level is measured between first and second portions of a substrate of a NOx adsorber, wherein the second NOx level is measured upstream from the first portion of the substrate, and wherein the first portion of the substrate is upstream from the second portion of the substrate. The regeneration control module initiates a regeneration cycle of the NOx adsorber when the first NOx level is greater than a predetermined percentage of the second NOx level, wherein the regeneration cycle includes injecting hydrocarbons (HC) into the exhaust stream at a location upstream from the NOx adsorber.

Abstract: An exhaust purification system for an internal combustion engine capable of lean-burn driving comprises: an NSR catalyst disposed in an exhaust passageway; an SCR disposed downstream of the NSR catalyst; a NOx sensor, disposed downstream of the SCR, for producing output in response to NOx concentration; and rich-spike means for causing a rich-spike. When the NOx sensor has produced output indicative of a NOx concentration higher than a given NOx concentration, the system increases the amount of the NOx contained in the exhaust gas discharged during the rich-spike. Under a given high-load condition, the air-fuel ratio is made stoichiometric during the rich-spike caused at a particular timing. Under a given low-load condition, the amount of exhaust gas is increased during the rich-spike.

Abstract: A failure of a filter is detected with a higher degree of accuracy. There are provided a filter that is arranged on an exhaust passage of an internal combustion engine for collecting a substance contained in an exhaust gas, a substance amount detection part that is arranged on the exhaust passage at a downstream side of the filter for detecting an amount of substance in the exhaust gas, a flow speed detection part that detects or estimates a flow speed of the exhaust gas which passes through the filter, and a determination part that makes a determination that the filter is in a failure, when the higher the flow speed of the exhaust gas passing through the filter, the larger a ratio of an amount of change in the amount of substance to an amount of change in the flow speed of the exhaust gas becomes.

Abstract: The present invention is directed to a gas particulate treatment system and may include a gas filter and a gas filter performance monitor downstream of the gas filter. The gas filter performance monitor includes a particulate trap operable to collect particulates passing through the gas filter, and a sensing apparatus associated with the gas filter performance monitor that operates to sense particulate collection in the gas filter performance monitor.

Abstract: An exhaust emission control apparatus for an internal combustion engine includes: an exhaust gas purification catalyst arranged in an exhaust gas passage of the internal combustion engine; an air/fuel ratio sensor installed on an upstream side of the exhaust gas purification catalyst and detects an air/fuel ratio of an exhaust gas discharged from the internal combustion engine; air/fuel ratio feedback control means that performs feedback control of the air/fuel ratio based on an output of the air/fuel ratio sensor; and sensor output correcting means that corrects a shift in the output of the air/fuel ratio sensor. The sensor output correcting means is configured so as to correct a shift in the output of the air/fuel ratio sensor using a lean shift amount of the air/fuel ratio sensor output in accordance with a quantity and/or a proportion of an aldehyde included in the exhaust gas.

Abstract: Disclosed embodiments include methods of removing carbon dioxide from combustion gas from an engine of a vehicle, systems for removing carbon dioxide from combustion gas from an engine of a vehicle, vehicles, methods of managing carbon dioxide emissions from an engine of a vehicle, and computer software program products for managing carbon dioxide emissions from an engine of a vehicle.

Abstract: In a method for operating an SCR catalytic converter provided for the reduction of NOx in exhaust gases of an internal combustion engine, which SCR catalytic converter is operated with a reagent which can be stored in the SCR catalytic converter such that there is a certain reagent fill level in the SCR catalytic converter, wherein the actual NOx concentration downstream of the SCR catalytic converter is monitored on the basis of the signal of a sensor, which is arranged downstream of the SCR catalytic converter and which is sensitive at least with respect to NOx, in comparison with a calculated NOx concentration downstream of the SCR catalytic converter, it is provided according to the invention that, in the case of a comparison result which represents a conversion deficit as a difference between the measured actual NOx concentration and the previous calculated reagent fill level in the SCR catalytic converter is corrected to a new calculated reagent fill level, whereby an immediate dosing of reagent takes p

Abstract: A method of correcting a soot mass estimate in a vehicle exhaust after-treatment device includes monitoring an exhaust gas pressure drop across a particulate filter included with the vehicle exhaust after-treatment device; determining an initial soot mass estimate from a monitored exhaust gas pressure drop; revising the initial soot mass estimate in view of a monitored engine speed, engine load, exhaust gas temperature, and NOx gas flow rate; and generating a particulate filter regeneration request if the revised soot mass estimate exceeds a threshold.

Abstract: A method of monitoring a differential pressure sensor of an exhaust gas aftertreatment system includes sensing a learned value (n?1, n, n+1, n+2, etc.) of the differential pressure sensor for each after-run occurrence of the vehicle, and calculating an absolute value of a rate of change between a current (n) learned value of the differential pressure sensor and a previous (n?1) learned value of the differential pressure sensor. The absolute value of the rate of change is compared to a threshold pressure value to determine if the absolute value of the rate of change is greater than the threshold pressure value or is less than the threshold pressure value. A fault in the differential pressure sensor is signaled when the absolute value of the rate of change of the learned values is greater than the threshold pressure value.

Abstract: An exhaust gas purification device may deactivate at least one of cylinders to supply a gasoline particulate filter with sufficient air according to a driving condition of a gasoline engine, and a control method thereof and a control method thereof may include comparing a pressure difference of the gasoline particulate filter with a predetermined value, determining a cylinder that may be to be deactivated when the pressure difference may be larger than the predetermined value, regenerating the gasoline particulate filter by supplying it with air through the deactivated cylinder, determining whether the engine may be in an over-run condition during the regeneration process, and returning to a general driving condition in a case that the engine may be in the over-run condition.

Abstract: A power system includes a dual fuel engine, a first fuel source configured to provide a first fuel to the engine, and a second fuel source configured to provide a second fuel to the engine different than the first fuel. The power system also includes an exhaust system configured to receive combustion exhaust from the engine. The exhaust system includes a reduction catalyst comprising palladium catalyst material and an oxidation catalyst comprising cobalt catalyst material. Additionally, changing a ratio of the first fuel provided to the engine relative to the second fuel changes a NOx conversion efficiency of the reduction catalyst.

Abstract: An exhaust system for use with an engine is disclosed. The exhaust system may have a first treatment device situated to receive a flow of exhaust and convert a first constituent of the exhaust to a second constituent, and a second treatment device located downstream of the first treatment device to reduce the first and second constituents. The exhaust system may also have a sensor configured to generate a signal indicative of one of a temperature and an oxygen concentration of the exhaust, and a controller in communication with the sensor. The controller may be configured to vary the other of the temperature and the oxygen concentration based on the signal such that a desired amount of the first constituent is converted to the second constituent by the first treatment device prior to reduction by the second treatment device.

Abstract: A method is provided for the determination of a NOx concentration value upstream of a Selective Catalytic Reduction (SCR) catalyst in a Diesel engine, the engine having an exhaust line, a Diesel Particulate Filter and a NOx concentration sensor downstream of the SCR catalyst, the method including, but is not limited to estimating the NOx concentration value upstream of the SCR catalyst as a function of at least two engine parameters, measuring the NOx concentration downstream of the SCR catalyst, calculating the difference Z(x, y) between the estimated NOx concentration value and the measured value and, in case the difference is higher than a predetermined threshold, correcting the estimated NOx concentration value with a NOx concentration correction value. The NOx concentration correction value is calculated using a correction map that correlates the at least two engine parameters and the difference Z(x, y) with the NOx concentration correction value.

Abstract: Embodiments for determining NH3 slip past a catalyst are provided. In one example, a filtering method for a NOx sensor of an exhaust gas system having an SCR catalytic converter comprises determining NOx concentration upstream of the catalytic converter, measuring NOx concentration downstream of the catalytic converter, modeling NOx conversion, modeling NH3 slip behavior, calculating a NOx error of the NOx modeling, calculating an NH3 error of the NH3 modeling, assigning data of the NOx sensor as NH3 measured values when a ratio of the NOx error to the NH3 error is greater than an upper threshold value, and assigning data of the NOx sensor as NOx measured values when the ratio of the NOx error to the NH3 error is smaller than a lower threshold value. In this way, NOx slip and NH3 slip may be determined from a common sensor.

Abstract: Methods systems and device for detecting humidity in air through use of an ammonia sensor included in the exhaust of an engine, such as a diesel engine are provided. In one example, a method for an engine having an exhaust with an ammonia sensor includes adjusting an operating parameter in response to ambient humidity, the ambient humidity based on a first ammonia sensor reading at a first exhaust air-fuel-ratio and a second ammonia sensor reading at a second exhaust air-fuel-ratio.

Abstract: A method of assessing overall efficiency of a selective-catalytic-reduction catalyst includes monitoring instantaneous efficiency of the catalyst. The method also includes determining the overall efficiency by summing instantaneous efficiency values weighted by a first set of coefficients if the most recent instantaneous efficiency value is above an instantaneous efficiency threshold. The method additionally includes determining the overall efficiency by summing instantaneous efficiency values weighted by a second set of coefficients if the most recent instantaneous efficiency value is equal to or below the instantaneous efficiency threshold. Furthermore, the method includes determining whether the overall efficiency has dropped below an overall efficiency threshold and reporting when the overall efficiency has dropped below the overall efficiency threshold.

Abstract: A catalyst deterioration diagnostic device for a multiple-cylinder internal combustion engine including a first cylinder group having exhaust system that is equipped with an exhaust gas recirculation (EGR) device with an EGR catalyst and a second cylinder group having exhaust system that is not equipped with the EGR device. The catalyst deterioration diagnostic device implements active air-fuel ratio control to diagnose deterioration of a main catalyst. During the active air-fuel ratio control, the catalyst deterioration diagnostic device oscillates only a target air-fuel ratio of the second cylinder group, without oscillating a target air-fuel ratio of the first cylinder group, in a case where the EGR device is stopped.

Abstract: A method for controlling a particulate matter sensor heater is provided. The method includes operating the heater to burn-off soot accumulated on the sensor; and adjusting the heater level based on sensor output generated during the heater operation. In this way, improved heater control can be achieved using the sensor output already available.

Abstract: An exhaust gas purifying system for an internal combustion engine has a relatively simple construction and is capable of accurately calculating the amount of SOx deposited on a NOx catalyst. A CO2 sensor having a detection electrode containing BaCO3 is disposed in an intake pipe at a location downstream of a confluent portion. A catalyst SOx deposition amount is calculated according to an EGR rate and a sensor deposition amount, based on the fact that the relationship between the sensor deposition amount detected by the CO2 sensor and the catalyst SOx deposition amount is determined according to the EGR rate.

Abstract: A method includes providing an exhaust stream for an internal combustion engine, where the exhaust stream is fluidly coupled to an aftertreatment component. The method includes optically determining an amount of an exhaust gas constituent in the exhaust stream. The method further includes modifying a model stored on a computer readable medium in response to the amount of the exhaust gas constituent. The model is an engine NOx generation model, a catalyst NOx storage model, a catalyst NOx conversion model, a catalyst NO to NO2 conversion model, a catalyst conversion efficiency model, an engine soot generation model, and/or a urea hydrolysis model.

Abstract: The present detector for detecting sulfur components includes a storage portion for storing SOx and NOx in the exhaust gas passing through an exhaust passage, in which the more an amount of stored SOx increases, the more an amount of stored NOx decreases, and which does not release SOx but release NOx at a set temperature, and a temperature sensor, estimates the amount of stored SOx on the basis of a relationship between, after the storage portion becomes the set temperature by heating, a heating pattern of the storage portion and temperature change of the storage portion measured by the temperature sensor, and detects an integrated amount of SOx passing through the exhaust passage during a given period or an value on the basis of the integrated amount.