Abstract: A lean-burn internal combustion engine and an exhaust aftertreatment system having an oxidation catalyst are described. A controller determines a fueling rate and a mass flowrate of the exhaust gas feedstream. An inlet temperature of the exhaust gas feedstream upstream of the oxidation catalyst is determined via the first temperature sensor, and an in-use outlet temperature of the exhaust gas feedstream is determined downstream of the oxidation catalyst via the second temperature sensor. An expected outlet temperature from the oxidation catalyst is determined based upon the inlet temperature, the fueling rate, and the mass flowrate of the exhaust gas feedstream. The oxidation catalyst is evaluated based upon the expected outlet temperature and the in-use outlet temperature.

Abstract: A lean-burn internal combustion engine and an exhaust aftertreatment system having an oxidation catalyst are described. A controller determines a fueling rate and a mass flowrate of the exhaust gas feedstream. An inlet temperature of the exhaust gas feedstream upstream of the oxidation catalyst is determined via the first temperature sensor, and an in-use outlet temperature of the exhaust gas feedstream is determined downstream of the oxidation catalyst via the second temperature sensor. An expected outlet temperature from the oxidation catalyst is determined based upon the inlet temperature, the fueling rate, and the mass flowrate of the exhaust gas feedstream. The oxidation catalyst is evaluated based upon the expected outlet temperature and the in-use outlet temperature.

Abstract: A system comprising an aftertreatment system comprising: a catalyst member, and a first exhaust conduit upstream of the catalyst member; a first temperature sensor operatively coupled to the catalyst member; a flow sensor coupled to the first exhaust conduit; and a controller. The controller determines a temperature of the catalyst member, a flow rate of exhaust within the first exhaust conduit, and a space velocity of the exhaust within the catalyst member. The controller determines a first degradation value indicative of a degradation of the catalyst member. The controller determines a first difference between the first degradation value and a first degradation reference value and a second difference between the first degradation value and a second degradation reference value. After determining that the first difference is less than the second difference, the controller selects a first calibration metric. The controller determines a first efficiency value associated with the catalyst member.

Abstract: Methods and systems are provided for operating an engine of a vehicle. In one example, a method may include positioning an oxygen sensor in an engine exhaust downstream from a selective catalytic reduction (SCR) catalyst, determining an oxygen storage capacity of the SCR catalyst based on a measurement of the oxygen sensor, and determining an extent of deactivation of the SCR catalyst based on the oxygen storage capacity.

Abstract: A system and method of determining system status in a vehicle system. The method including collecting, by a computing system, a plurality of data associated with a test specimen and the vehicle system, selecting a relevant data set of the plurality of data, the selecting based on at least one correlation coefficient associated with the plurality of data, and transforming at least a portion of the selected relevant data to form a transformed data set, the transforming based on mathematical properties. The method also includes collecting statistics associated with the selected relevant data set and the transformed data set to form a statistics data set, classifying the selected relevant data set, transformed data set, and the statistics data set; and predicting a status of a system based on the classifying.

Abstract: Methods and/or systems for operating an exhaust-gas aftertreatment system of an internal combustion engine include: setting the internal combustion engine to a diagnostic operating mode with relevant diagnostic operating parameters of the internal combustion engine are set to correspond with diagnostic default values; inducing a targeted, defined NH3 and/or NOX concentration change upstream of the filter; measuring the NH3 and/or NOX concentration change downstream of the filter; providing a correlating concentration comparison value; evaluating the concentration change on the basis of the respective concentration comparison value and predefined limit values; and diagnosing the SCR particle filter as defective if the evaluation yields that the concentration comparison value has overshot a predefined limit value.

Abstract: A method for measuring TOC in test water is disclosed. Test water is injected into a combustion tube, which is controlled to be heated in a state of flowing carrier air generated by discharging stored water filled in a combustion gas or carrier air storage tank. After the drying process, temperature in the combustion tube is increased, and the dried organic carbon is burned. Combustion gas is guided to the combustion gas storage tank. An inside of the combustion tube is purified due to high pressure steam generated by injecting pure water and organic carbon removed in the purification process is burned and oxidized. The generated combustion gas is guided to the combustion gas storage tank and is pushed into an infrared meter to measure a carbon dioxide gas concentration. Otherwise, the generated combustion gas is guided to the infrared meter to measure the carbon dioxide gas concentration.

Abstract: Methods, systems, and vehicles that control the temperature of a device included in the vehicle are presented herein. The temperature of the device is controlled by ventilating the device with drivetrain air, such as transmission cooling air. In some embodiments, the device is at a greater temperature than the drivetrain air, which cools the device. In other embodiments, the device is at a lesser temperature than the drivetrain air, which heats the device. The drivetrain air is provided to the device through an exhaust duct coupled to the vehicle's transmission. The drivetrain exhaust air is preferably circulated by the transmission. The transmission may be a continuously variable transmission. The device may be an oxygen sensor that is coupled to an engine exhaust pipe. The oxygen sensor is thermally coupled to the engine exhaust and the engine exhaust pipe, which are at greater temperatures than the transmission exhaust air.

Abstract: The invention relates to a method for starting an internal combustion engine, the exhaust gas system of which is equipped with an electrically heatable lambda sensor and a catalytic converter with an oxygen reservoir. The combination of method steps according to the invention allows the internal combustion engine to be started with an optimal raw emission reduction directly after a cold start and an optimal pollutant conversion in the warm-up phase. The invention likewise relates to a motor vehicle with an internal combustion engine comprising an exhaust gas system having an electrically heatable lambda sensor and a catalytic converter with an oxygen reservoir, and comprising a controller, wherein the controller is designed to carry out the method according to the invention.

Abstract: 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.

Abstract: A regeneration control device controlling a temperature increase unit of an exhaust gas treatment device including a DOC disposed in an exhaust passage of a diesel engine to regenerate the exhaust gas treatment device includes: a DOC temperature-increase-necessary-state detection part detecting a temperature increase necessary state including at least one of a blockage state, detected on the basis of comparison between a blockage parameter related to blockage of the DOC and a predetermined blockage threshold, of the DOC or a blockage risk state, detected when the diesel engine is in an operating state that is likely to cause blockage of the DOC, of the DOC; and a DOC temperature increase execution part executing a DOC temperature increase control including: a first temperature increase process to control the temperature increase unit, if the temperature increase necessary state of the DOC is detected, so as to increase the temperature of the DOC to a first temperature at which the DOC activates; and a second

Abstract: An exhaust gas temperature sensor diagnostic system includes an exhaust gas temperature sensor, a controller and a storage device. The controller is programmed to wakeup after a predetermined time after engine shutdown, determine a temperature of the sensor and ambient temperature, calculate a difference in the temperature of the sensor after wakeup to a temperature of the sensor at engine shutdown, determine an estimated temperature of the sensor based on the ambient temperature and the predetermined time, add the difference in the temperature of the sensor at wakeup to the estimated temperature to determine a compensated estimated sensor reading, determine a difference between the compensated estimated sensor reading and a corrected sensor reading, compare the difference between the compensated estimated sensor reading and a corrected sensor reading to a threshold to determine whether the sensor is operating properly. The storage device is configured to store information related to the sensor.

Abstract: A system (9) of the invention is a system for detecting deterioration of a catalyst (8) provided in an exhaust passage (12) of an internal combustion engine (11), the system including: means (5) that detects a temperature of an exhaust on an upstream side of the catalyst (8); means (6) that detects a temperature of the exhaust on a downstream side of the catalyst (8); a recognition unit (10) that recognizes, both upstream and downstream of the catalyst (8), a change point at which the temperature changes from temperature fall or constant temperature to temperature rise during acceleration operation, or a change point at which the temperature changes from temperature rise or constant temperature to temperature fall during deceleration operation; and a determination unit (10) that determines that the catalyst (8) has deteriorated when a difference (?T or ?T?) between the upstream and downstream change points becomes equal to or longer than a predetermined time.

Abstract: In an engine device having a urea mixing pipe which injects urea water into exhaust gas of an engine, and an SCR case which removes nitrogen oxides in the exhaust gas of the engine, and structured such that an inlet side of the SCR case is connected to an outlet side of the urea mixing pipe, an exhaust gas outlet side of the SCR case is connected to an exhaust gas inlet side of the urea mixing pipe where a urea water injection means is arranged, and an exhaust gas inlet side of the urea mixing pipe is supported to the exhaust gas outlet side of the SCR case.

Abstract: A self-correcting exhaust gas temperature sensor system includes an exhaust gas temperature sensor, a controller and a storage device. The exhaust gas temperature sensor is configured to be disposed in an exhaust manifold of a vehicle. The controller is programmed to determine a reading of the exhaust gas temperature sensor at a predetermined time, determine a comparative temperature value, calculate an offset difference between the comparative temperature value and the reading of the exhaust gas temperature sensor, and based on the offset difference relative of the comparative temperature value, replace an exhaust gas temperature sensor offset value with the offset difference or with a threshold value. The storage device is configured to store the offset difference or the threshold value.

Abstract: A method and system is disclosed to test for a proper functioning of a selective catalytic reduction system of an internal combustion engine. The engine is operated at idle speed and a functionality check of the pressure sensor is executed. The engine is operated to increase an exhaust gas temperature in the exhaust pipe upstream of the catalyst and a functionality check of the pump is executed. A functionality check of the injector is executed after the functionality check of the pump and once the exhaust gas temperature has reached a predetermined target value thereof. A functionality check of the supply conduit is executed after the functionality check of the injector. The selective catalytic reduction system is identified as functioning properly when all of the functionality checks yields a positive result or malfunctioning when any one of the functionality checks yields a negative result.

Abstract: A purification controller 12 is configured to estimate the amount of ammonia occluded (i.e. ammonia occlusion amount) in an SCR catalyst 4, which is arranged in an exhaust pipe 52 of a diesel engine 51 so as to purify NOx in an exhaust gas of the diesel engine 51. More specifically, the purification controller 12 acquires upstream NO concentration data, upstream NO2 concentration data, downstream NOx concentration data, downstream NO2 concentration data and downstream ammonia concentration data. The purification controller 12 further acquires an urea injection amount. Then, the purification controller 12 estimates the ammonia occlusion amount based on the acquired upstream NO concentration data, upstream NO2 concentration data, downstream NOx concentration data, downstream NO2 concentration data and downstream ammonia concentration data, the acquired urea injection amount and reaction formulas for reduction of NOx with the SCR catalyst 4.

Abstract: A diagnostic device includes: a diesel oxidation catalyst (DOC) for oxidizing hydrocarbon (HC) and nitrogen monoxide in an exhaust gas; a selective catalytic reduction (SCR) catalyst for reducing and purifying NOx contained in the exhaust gas; a NOx purification rate calculation unit which calculates, based on NOx values at upstream and downstream sides of the SCR catalyst, a low temperature NOx purification rate and a high temperature NOx purification rate; a HC heat generation rate calculation unit which calculates an HC purification rate based on at least the difference between the exhaust gas heat quantities at upstream and downstream sides of the DOC; and a deterioration determination unit which determines the deterioration in the NO2 producing capability of the DOC based on the calculated low temperature NOx purification rate, the calculated high temperature NOx purification rate, and the calculated HC purification rate.

Abstract: A determination of a quality of a reducing agent solution containing ammonia used to reduce nitrogen oxides involves actuating a metering unit that delivers metered quantities of reducing agent solution into an engine's discharged exhaust gas and determining an efficiency value that is at least correlated with the efficiency of the SCR catalytic converter and comparing the efficiency value to a predefinable limit value. If an efficiency value not corresponding to proper functioning of the SCR exhaust emission control system is identified by the comparison, a switch is made to a diagnostic mode in a second method step. If a predefinable deviation of the efficiency value from a limit value is identified after expiration of the second method step time period, a third method step is performed for conditioning the SCR catalytic converter. A fourth step involves an adaptation mode in which a deviation from the efficiency value is determined.

Abstract: System and method of treating exhaust gas from an internal combustion engine using selective catalytic reduction (SCR) and adaptive control of diesel exhaust fluid (DEF) injection. Adaptive control of DEF injection includes intentionally underdosing the injected DEF based on an amount of DEF determined by an electronic control unit as an amount needed to reduce nitrogen oxides (NOx) to a compliance threshold. Since underdosing prevents ammonia (NH3) slip from occurring due to low levels of DEF, a sensor accurately senses NOx present in the exhaust gas at an output of an SCR chamber. An electronic control unit increases the amount of injected DEF based on the sensor.

Abstract: Methods and systems are provided for determining degradation of a particulate filter in an exhaust conduit. In one example, a method may include diverting exhaust gas to a secondary soot sensor assembly downstream of a first filter, comprising a filter and determining degradation based on time intervals between subsequent filter regenerations of the second filter in the secondary soot sensor assembly.

Abstract: A method for operating an exhaust gas system of a motor vehicle involves performing regeneration of the particle filter as a function of at least one aging value characterizing an aging condition of the oxidation catalytic converter.

Abstract: A method for optimizing a gas conversion rate in a respiratory gas analyzer, more particularly for nitric oxide (NO) in the respiratory gas, and an associated device are disclosed.

Abstract: A powertrain includes a combustion chamber, an intake assembly, an exhaust manifold, and a pump. The combustion chamber is configured for combusting an air and fuel mixture. The intake assembly is configured to supply air to the combustion chamber. The exhaust manifold is configured to draw exhaust gas from the combustion chamber. The pump is operatively disposed between the intake assembly and the exhaust manifold such that the pump is in fluid communication with each of intake assembly and the exhaust manifold. The pump is configured to operate in a first mode to draw exhaust gas from the exhaust manifold and supply the exhaust gas to the intake manifold at a positive EGR flow rate such that exhaust gas is supplied to the combustion chamber.

Abstract: A method of ageing a catalyst material includes at least the steps of: (a) heating a gaseous stream; (b) adding a least one pure hydrocarbon gas and an oxygen-containing gas to the heated gaseous stream to provide a combined stream; and (c) passing the combined stream through the catalyst material. The use of at least one pure hydrocarbon gas and an oxygen-containing gas allows maximum re-circulation of the exit stream from the catalyst material for reuse, while maintaining the correct C, H and O proportions being provided in the combined stream to replicate realistic use of the catalyst material.

Abstract: The present invention relates to a method for operating an exhaust gas aftertreatment apparatus (13) of an internal combustion engine (11), which comprises an oxidation catalytic converter (29), an SCR catalytic converter (35) and a first temperature sensor (32) disposed in the direction of flow downstream of the oxidation catalytic converter (29) and upstream of the SCR catalytic converter (35), an exhaust gas atmosphere capable of exothermal reaction in said oxidation catalytic converter (29) being generated by the metering of hydrocarbons into the exhaust gas (3) upstream of said oxidation catalytic converter (29) during a heating operation.

Abstract: A method for determining if a selective catalytic reduction (SCR) device that is dosed with a reductant is being mis-dosed by considering an expected exhaust gas output state from the SCR device and measured exhaust gas output state, a NOx sensor sensitivity figure that is an indication of how sensitive the measured exhaust gas output state is to dosing errors and performing cross-correlation operations.

Abstract: Various embodiments include systems adapted to monitor catalyst deterioration. Some embodiments include a catalyst deterioration detection system including a pre-catalytic converter gas sensor, a post-catalytic converter gas sensor, at least one computing device in communication with the pre-catalytic converter and post-catalytic converter gas sensors, the at least one computing device configured to monitor catalyst deterioration by performing actions including estimating a catalyst gas storage level by comparing a difference between a pre-catalytic converter gas level from the pre-catalytic converter gas sensor and a post-catalytic converter gas level from the post-catalytic converter gas sensor, comparing the estimated catalyst gas storage level to a baseline catalyst gas storage level and determining that the catalyst is deteriorated in response to the baseline catalyst gas storage level exceeding the estimated gas storage level by a threshold difference.

Abstract: A device for diagnosing deterioration of a catalyst by a decrease in oxygen storage capacity, in which the oxygen storage capacity by which the catalyst deterioration is diagnosed to be present when exhaust gas recirculation is not implemented is higher than the oxygen storage capacity by which the catalyst deterioration is diagnosed to be present when the exhaust gas recirculation is implemented.

Abstract: A deterioration diagnosing system for an exhaust emission control catalyst of an engine is provided. The catalyst includes an HC adsorbing part and an oxidation catalyst part. The system includes an actual exhaust-emission-control-catalyst temperature parameter detecting module for detecting a parameter correlating with an actual exhaust-emission-control-catalyst temperature. The catalyst also includes a deterioration determining module for receiving a detection value from the actual exhaust-emission-control-catalyst temperature parameter detecting module when predetermined diagnosis executing conditions are met, and determining that the exhaust emission control catalyst is deteriorated when the detection value is smaller than a predetermined diagnostic temperature parameter threshold. The catalyst also includes an HC discharge amount calculating module for calculating an amount of discharging HC from the HC adsorbing part.

Abstract: A method for diagnosing reductant delivery performance of a reductant delivery system is provided. The method provides an outlet pressure sensor at a reductant outlet of the reductant delivery system and a virtual pressure sensor in an exhaust stream where reductant is injected into the stream. The method comprises calculating a downstream reductant flow rate using the outlet pressure sensor and the virtual pressure sensor; and calculating an upstream reductant flow rate within the reductant delivery system using at least one of a temperature sensor, a pressure sensor and a control valve. The calculated downstream and upstream reductant flow rates are compared, and diagnostics is conducted based the comparison to find the malfunctions in the reductant delivery system.

Abstract: An oxidation catalyst (OC)/hydrocarbon injector (HCI) testing system includes a controller having a first oxygen sensor input configured and disposed to receive a first oxygen sensor value upstream of an oxidation catalyst (OC) device and a second oxygen sensor input configured to receive a second oxygen sensor value downstream of the OC device. The controller is configured and disposed to perform a first test to detect one of a faulty OC device and a faulty HCI based on a difference between the first and second oxygen sensor values.

Abstract: A monitoring system for a single can oxidation catalyst (OC)/particulate filter (PF) member includes a controller including a first temperature sensor input configured to receive a first exhaust temperature upstream of an OC portion of the single can OC/PF member, a second temperature sensor input configured to receive a second exhaust temperature downstream of the first temperature. The controller is configured and disposed to calculate an exothermic capacity of the OC portion and determine washcoat deterioration of a PF portion of the single can OC/PF member based on the exothermic capacity of the OC portion.

Abstract: A competence diagnosis system for a urea water temperature sensor that can prevent a misdiagnosis when urea water is replenished in a urea tank. The system includes a urea water level condition determination unit that stores a urea water level, which is measured by a level sensor provided in the urea tank, in a storage unit immediately before key-off, obtains a level difference between the urea water level stored in the storage unit and a current urea water level after key-on, and allows a diagnosis by the competence diagnosis unit through temperature comparison when the level difference is less than or equal to a predetermined threshold value.

Abstract: A vehicle and a method of updating efficiency of a selective catalytic reduction filter (SCRF) of an exhaust treatment system of the vehicle are disclosed. The method includes obtaining an initial calculated efficiency of the SCRF, via a controller, regarding one of a NOx conversion, a reductant absorption, a reductant desorption and a reductant oxidation. The method also includes determining a soot mass estimate in the SCRF representative of an amount of soot collected inside the SCRF and determining a soot correction factor from the soot mass estimate. The method further includes calculating, via the controller, an updated efficiency value of the SCRF by multiplying the soot correction factor and the initial calculated efficiency to update efficiency of the SCRF.

Abstract: A method and an arrangement for monitoring an exhaust system of an internal combustion engine. Temperature profiles upstream and downstream of an installation location of a catalytic converter are measured in order to determine whether or not a catalytic converter is installed.

Abstract: In a control device for an internal combustion engine including an air-fuel ratio sensor that includes a catalyst layer that covers an exhaust gas-side electrode, an oxygen storage capacity of the catalyst layer is acquired based on a sensor output of the air-fuel ratio sensor. The sensor output is corrected if the oxygen storage capacity is higher than a predetermined value and the sensor output is in a predetermined range in the vicinity of the theoretical air-fuel ratio. Preferably, the oxygen storage capacity is calculated by integrating the product of a deviation amount ?A/F of the sensor output with respect to the theoretical air-fuel ratio and a dwell time thereof. A correction period in which a correction operation is performed is set based on the oxygen storage capacity.

Abstract: A method of estimating a total amount of soot in a diesel particulate filter includes monitoring a pressure differential across the diesel particulate filter; monitoring an engine speed and an engine load from an engine in fluid communication with the diesel particulate filter; determining a first soot mass estimate from the monitored pressure differential, the first soot mass estimate having an associated confidence indicator based on the monitored engine speed and engine load; determining a second soot mass estimate from the monitored engine speed and engine load; and outputting the first soot mass estimate if the confidence indicator is above a predetermined threshold, and outputting the second soot mass estimate if the confidence indicator is below the predetermined threshold.

Abstract: A delivery unit for delivering a liquid additive in a motor vehicle, includes at least one temperature sensor for contactlessly measuring a temperature at least at one measurement point in the delivery unit. The temperature sensor and the measurement point have a spacing therebetween and a radiation channel which is free from fixtures is provided between the temperature sensor and the measurement point. A method for checking the operating state of a delivery unit and a motor vehicle having a delivery unit are also provided.

Abstract: A system for a vehicle includes a first ozone sensor that generates a first sensor signal indicating a first amount of ozone in air flowing into a radiator. A second ozone sensor generates a second sensor signal indicating a second amount of ozone in air flowing out of the radiator. A control module receives the first sensor signal and the second sensor signal and determines an ozone conversion rate based on the first sensor signal and the second sensor signal.

Abstract: An exhaust aftertreatment system includes an exhaust aftertreatment component housing and a sensor table coupled to an exterior surface of the exhaust aftertreatment component housing. The sensor table includes a base including footings and a first platform offset from the footings by first standoffs so to define a first air gap. The base also includes second standoffs extending from the first platform. The sensor table also includes a top plate including a second platform and third standoffs extending from the second platform. The second platform is fixedly coupled to the second standoffs so to define a second air gap between the first platform and the second platform. The sensor table further includes a first sensor module coupled to the third standoffs so to define a third air gap between the second platform and the first sensor module.

Abstract: The invention relates to a method for diagnosing the performance of a catalytic converter (3) of a petrol automobile onboard the vehicle, the catalytic converter being mounted on the exhaust line (1) of the vehicle, wherein said method comprises placing two oxygen probes (5, 6) on the exhaust line (1) upstream and downstream from the converter (3), respectively, analysing the signals (7, 16) thereof, and comparing the signal (16) of the downstream probe (6) with a threshold in order to carry out a passive diagnosis during a first period of the lifespan of the converter (3), after which, during a last period of the converter (3) lifespan, an intrusive diagnosis of the converter (3) performance is carried out using the two probes (5, 6) and a diagnosis automaton, by measuring the oxygen storage capacity of the converter (3).

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 holding jig has a tubular jig base member, and a tubular expansion/contraction member disposed on an inner peripheral surface side of the tubular jig base member. Both end sides of the tubular expansion/contraction member are fixed to both end sides of the tubular jig base member along the whole periphery. A configuration of an inner peripheral surface of the tubular expansion/contraction member is smaller than a surface configuration of a pillar-like body (a honeycomb structure) to be held. On the other hand, a configuration of an inner peripheral surface of the tubular jig base member is larger than the surface configuration of the pillar-like body (the honeycomb structure) to be held.

Abstract: A method of estimating a total amount of soot in a diesel particulate filter includes monitoring a pressure differential across the diesel particulate filter; monitoring an engine speed and an engine load from an engine in fluid communication with the diesel particulate filter; determining a first soot mass estimate from the monitored pressure differential, the first soot mass estimate having an associated confidence indicator based on the monitored engine speed and engine load; determining a second soot mass estimate from the monitored engine speed and engine load; and outputting the first soot mass estimate if the confidence indicator is above a predetermined threshold, and outputting the second soot mass estimate if the confidence indicator is below the predetermined threshold.

Abstract: An engine diagnostic tool includes a diagnostic engine calibration module structured to include a plurality of diagnostic processes for operating an internal combustion engine system of an immobilized vehicle. One or more of the plurality of diagnostic processes are structured to be an intrusive diagnostic process for the internal combustion engine system, wherein the intrusive diagnostic process causes the internal combustion engine system to operate outside of one or more calibration parameters. The diagnostic engine module is further structured to control the order and timing of each diagnostic process in the plurality of diagnostic processes.

Abstract: An exhaust diagnostic system comprises a selective catalyst reduction (SCR) component testing module, an exhaust stream temperature management module, and a test enabling module. The component testing module executes an SCR component efficiency test. The exhaust stream temperature management module adjusts a temperature of the SCR component to a predetermined temperature range. The test enabling module executes a process for depleting a reductant load and subsequently initiates an SCR component efficiency test while the temperature of the SCR catalyst is within the predetermined temperature range. A method for diagnosing an exhaust system comprises determining an efficiency of an SCR component and selectively adjusting a temperature of the SCR component to a predetermined temperature range. The method also includes executing a process for depleting a reductant load and initiating an SCR component efficiency test while the temperature of the SCR component is within the predetermined temperature range.

Abstract: An abnormality detecting device of an internal combustion engine according to the present invention includes a sensor nick abnormality detecting unit configured to detect a nick abnormality in a detecting element of a downstream side sensor which is provided in a downstream side of an exhaust gas purifying catalyst in an exhaust passage and generates an output corresponding to an oxygen concentration in exhaust gas, on the basis of a matter that a distribution of an output of the downstream side sensor is biased to an area in which the air-fuel ratio is leaner than a theoretical air-fuel ratio, and an inhibiting unit configured to inhibit detection of the nick abnormality of the detecting element by the sensor nick abnormality detecting unit in the case that an intake air amount exceeds a predetermined amount.

Abstract: A method of monitoring catalyst performance may comprise applying a set of parameter readings for a given sample to a support vector machine to generate a classification output, clustering the set of parameter readings to reduce a number of support vectors, computing a total fuel mass following a deceleration fuel shut-off event and an exhaust gas oxygen sensor switch and indicating catalyst degradation based on the total fuel mass.

Abstract: An exhaust gas treatment system for an internal combustion engine may have a reductant delivery system with a controller that performs period diagnostics to determine whether there is a blockage in the reductant delivery system. The diagnostic procedure may include sampling first and second pressures at first and second operating conditions, respectively, and then comparing the first pressure differential between the first and second pressures with one or more threshold pressure differentials to determine whether system components such as a dosing line and an injector are at least partially blocked. If such a test is not conclusive, it may be repeated at a third and fourth operating conditions to provide a second pressure differential. The offset between the first and second pressure differentials may also be used to help diagnose where a blockage in the system resides.