Abstract: A system for purging a device for injecting fuel into an exhaust system of an engine comprising a device having an input and an output coupled to an exhaust system, at least one air valve and at least one fuel valve. The air valve has an input an input coupled to an air supply and an output coupled to the device through a check valve. The fuel valve has an input coupled to a fuel supply and an output coupled to the device through a check valve. When the air valve is open and the fuel valve is closed, air flows from the air supply to the device and is injected into the exhaust system of the engine. When the air valve is closed and the fuel valve is open, fuel flows from the fuel supply to the device and is injected into the exhaust system of the engine.

Abstract: A vehicle control device applied to a vehicle including an internal combustion engine and an electrically heated catalyst which is warmed by applying a current, and includes a catalyst carrier supporting a catalyst and a carrier retention unit that retains the catalyst carrier and has an electrical insulation property. The control unit performs a control of suppressing a supply of an unburned gas from the internal combustion engine to the electrically heated catalyst so that the carrier retention unit is maintained at a lower temperature than the catalyst, when a condition for performing a fuel cut of the internal combustion engine during a deceleration is satisfied. Therefore, it is possible to suppress a rapid cooling of the catalyst, and it becomes possible to maintain a temperature of the carrier retention unit at a lower temperature than a temperature of the catalyst.

Abstract: A diagnostic test for a secondary air system comprising an air pump, a first mass air flow sensor connected to the air pump and a first check valve connected to the first mass air flow sensor. A first testing phase is disclosed comprising a first delay period and a first testing period, wherein the air pump is activated. A second testing phase is disclosed comprising a second delay period and a second testing period wherein the first check valve is opened. A third testing phase comprising a third delay period and a third testing period is disclosed wherein the first check valve is closed. A fourth testing phase is disclosed comprising a fourth delay period and a fourth testing period wherein the air pump is deactivated. An optional fifth testing phase is also disclosed comprising a fifth delay period and a fifth testing period wherein the air pump remains off but the check valve is reopened and engine RPMs are increased.

Abstract: An exhaust system for an internal combustion engine is provided. The engine comprises an exhaust line, at least one exhaust gas aftertreatment device arranged in the exhaust line, and a heat source and a heat sink arranged in separate branches of the exhaust line upstream of the exhaust gas aftertreatment device, an exhaust gas flow rate through each respective separate exhaust branch controlled by at least one flow control device. In this way, the temperature of the exhaust entering the aftertreatment device may be controlled by an amount of exhaust that flows through each branch of the exhaust line.

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: An exhaust treatment system for an engine includes a selective catalyst reduction (SCR) treatment module that controls a valve and an air pump to deliver air to an SCR catalyst in response to the engine turning off. An SCR loading module controls the valve and the air pump to deliver air to an exhaust manifold and controls a dosing system to deliver a dosing agent upstream of the SCR catalyst when a temperature of the SCR catalyst is less than a temperature threshold and the SCR catalyst is not saturated with ammonia.

Abstract: A secondary air injection system supplying some of air introduced into an intake manifold to an exhaust manifold may include: an electric supercharger compressing air introduced through an air duct; throttle valves installed at an upstream of the intake manifold and controlling the amount of air introduced into the intake manifold by controlling the amount of air passing through the electric supercharger; secondary air valves installed on branching paths branched from intake, lines that link the electric supercharger and the throttle vales and controlling the amount of air for secondary air injection; and an injector that post-combusts exhaust gas discharged from an engine by injecting secondary air passing through the secondary air valve to a runner of the manifold.

Abstract: A regeneration apparatus comprises a heater 2 which heats a catalyst 1 at the time of stopping fuel supply to an engine, a pump 4 which supplies an oxidizing gas or a reducing gas to the heated catalyst 1 and a switching valve 3. In the oxidizing step, catalytic poisons, for example hydrocarbon, which are absorbed on a noble metal are oxidized and removed. The particles of the noble metal become oxidized particles as pure oxide and the like. After the oxidizing step, the reducing step is carried out. In the reducing step, particles of the noble metal are reduced and re-dispersed on the support simultaneously and as a result, the particles of the noble metal become fine. Thus, a deteriorated catalyst can be regenerated without interrupting the use of catalyst and also without deteriorating the drivability.

Abstract: An assembly and method for reducing nitrogen oxides, carbon monoxide and hydrocarbons in exhausts of internal combustion engines, wherein the exhaust is acted upon in a first stage catalytic converter. A first portion of the first stage catalytic converter output is cooled and a second portion of the catalytic converter output is not cooled. The cooled and not cooled exhausts are united and directed to a second stage catalytic converter. Air is injected into a selected one of (1) the not cooled exhaust prior to the juncture thereof with the cooled exhaust, and (2) the combined cooled and not cooled exhausts after the juncture thereof.

Abstract: An air-assisted fluid injector has an injector housing having a nozzle bore and an injector nozzle sealably disposed in the nozzle bore and having an exposed injector face on one end that projects from an end of the nozzle bore, the injector nozzle having a fluid conduit on an other end that extends from a fluid inlet toward the injector face and that opens into a plurality of fluid outlet conduits that extend to a corresponding plurality of fluid outlets spaced apart on the injector face and operable to provide a predetermined spray pattern. The injector also includes an air conduit having an air inlet on the other end of the injector nozzle extending through the injector housing and opening into a plurality of air conduit outlets proximate the injector face, each air conduit outlet extending to and opening into a respective fluid conduit outlet.

Abstract: An exhaust purification device for an internal combustion engine is provided that can promote the reduction of NOx in a NOx purification catalyst from immediately after startup of the internal combustion engine.

Abstract: A control system for an engine includes an exhaust module and a combustion module. The exhaust module supplies a first MAF to exhaust produced by the engine upstream of a catalytic converter during regeneration of a PM filter located downstream of the catalytic converter. The combustion module, during the regeneration, supplies a first amount of fuel to a cylinder during an intake stroke based on the first MAF and a second MAF to the cylinder during the intake stroke. The combustion module, during the regeneration, further supplies a second amount of fuel to the cylinder during a subsequent intake stroke based on a first A/F ratio of the cylinder and an oxygen content of the exhaust downstream of the catalytic converter. A method for controlling an engine during regeneration of the PM filter is also provided.

Abstract: Provided is an exhaust-treatment device for a diesel engine, said device being capable of suppressing engine noise. In a first stage P1 of an exhaust-temperature-raising process, a target engine speed is set to a prescribed first target speed R1 and an intake throttle valve 41 is set to a prescribed first degree of opening O1. In a second stage P2, the target engine speed is maintained at the first target speed R1 and the intake throttle valve 41 is set to a position more closed than the first degree of opening O1. When a set duration T2 for the second stage P2 has come to an end, the intake throttle valve 41 is at a second degree of opening O2, which is maintained in third and subsequent stages P3/P4. In said third and subsequent stages P3/P4, as a set duration T3/T4 for each stage P3/P4 passes, the target engine speed is updated to a target speed R2/R3 higher than the target speed R1/R2 during the immediately prior stage P2/P3, and the temperature of DPF1 upstream exhaust gas 12 is increased.

Abstract: A device for purification of exhaust gas including: an exhaust gas passage 15 connected to an internal combustion engine 10; a particulate matter trapping device 30 which is disposed in the exhaust gas passage 15, and which traps particulate matters in exhaust gas; ozone supply means 40 which is connected to the exhaust gas passage 15 and on an upstream side of the particulate matter trapping device 30, and which can supply ozone to the particulate matter trapping device 30; and an NO oxidizing catalyst 20 which is disposed in the exhaust gas passage 15 and on an upstream of the ozone supply means 40, and which oxidizes NO in the exhaust gas.

Abstract: A muffler for a combustion engine includes walls forming a chamber, a first inlet, a first outlet, and a conduit. The first inlet is designed to receive exhaust gases from an exhaust duct of the engine. The exhaust gases pass through the chamber when moving from the first inlet to the first outlet. The exhaust gases then exit the muffler through the first outlet. The conduit extends between a second inlet and a second outlet. The second inlet is configured to receive fresh air entering the muffler. The fresh air then exits the conduit and is introduced into the exhaust gases through the second outlet.

Abstract: An internal combustion engine includes an exhaust treatment apparatus provided in an exhaust passage and a burner apparatus provided upstream of the exhaust treatment apparatus. The burner apparatus includes a fuel addition valve which adds fuel into the exhaust passage, heating means for heating the fuel added by the fuel addition valve, and a small-sized oxidation catalyst provided in the exhaust passage downstream of the heating means. The amount of fuel added by the fuel addition valve per predetermined unit time is controlled to control the position of an ignition point where the added fuel is ignited. Thus, the small-sized oxidation catalyst and the exhaust treatment apparatus can be efficiently warmed up.

Abstract: A warming-up system performing a catalytic converter warming-up method has an electric motor (1m) enabling a turbocharger (1) to increase the amount of air supplied to an internal combustion engine (2) regardless of the amount of exhaust gas flowing through a turbine (1t) of the turbocharger (1), a variable nozzle (1n) regulating the flow of exhaust gas through the turbine (1t), and an ECU (5) for controlling the operation of the electric motor (1m) and the variable nozzle (1n) and the amount of fuel supplied to the internal combustion engine (2). After the internal combustion engine (2) is started, the ECU (5) warms up the catalytic converter (4) by driving the electrical motor (1m) to forcibly rotate the turbine (1t), opening the variable nozzle (1n), and increasing fuel supply to the internal combustion engine (2).

Abstract: An engine system includes an engine with a secondary air source, a fuel system that communicates with the engine, and a controller that communicates with the fuel system. The controller controls a first quantity of liquid fuel to the engine at a first A/F ratio and a second quantity of vapor fuel to the engine at a second A/F ratio. The liquid and vapor fuel mixture has a third A/F ratio. A secondary air source provides additional air to the third A/F ratio. The controller determines an available A/F ratio of vapor fuel within the fuel tank and performs a comparison with a target A/F ratio range. The second quantity is set to zero if the A/F ratio of the vapor fuel is outside of the target A/F ratio range. The controller adjusts the first and second quantities based on a comparison between an exhaust A/F ratio and a target exhaust A/F ratio.

Abstract: A secondary air system for the supply of secondary air into at least one exhaust gas outlet passage of a cylinder head of an internal combustion engine, wherein at least one secondary air passage provided in the cylinder head is associated with the exhaust gas outlet passage and opens into the exhaust gas outlet passage and into an outer connection surface of the cylinder head. A base plate is provided which can be placed onto the connection surface of the cylinder head and which is provided with secondary air stubs which each engage into a secondary air passage when the base plate is in place. The base plate is provided on its outer side remote from the connection side with at least one hood via which the supplied secondary air is distributed to a plurality of secondary air stubs.

Abstract: An exhaust gas purification device for an internal combustion engine, in which a catalyst installed in an exhaust passage is quickly heated to the activation temperature of the catalyst.

Abstract: There is provided a control apparatus for an internal combustion engine, which can favorably reduce a load necessary for cranking at the time of the next start, while preventing the fresh air inflow to a catalyst at the time of the stop of the internal combustion engine. A valve stop command is issued to an electrically-driven actuator so that the operational states of intake and exhaust valves becomes a valve closed/stopped state when fuel supply is stopped in response to an establishment of a predetermined stop condition of the internal combustion engine. Then, to return the operational states of the intake and exhaust valves to a valve operating state after the completion of the stopping operation of the internal combustion engine, a valve return command is issued to the actuator, and a crankshaft is rotationally driven by a predetermined angle required to return the operational states of the intake and exhaust valves to the valve operating state.

Abstract: An internal combustion engine control apparatus includes: a purge control unit causing fuel evaporative emission to be introduced into an intake passage to attain a purge flow rate based on a pressure in the intake passage; a fuel cut return rich control unit setting a rich target air-fuel ratio when returning from fuel cut, and feedback-controlling a fuel supply rate on the basis of the target air-fuel ratio, purge flow rate and intake air flow rate to attain the target air-fuel ratio; a fuel increase upper limit setting unit setting an allowable upper limit for an increase in fuel supply rate in fuel cut return rich control; and an actual air-fuel ratio control unit controlling an actual air-fuel ratio to a richer side when the fuel supply rate in the fuel cut return rich control has reached the allowable upper limit and the actual air-fuel ratio is lean.

Abstract: Systems and methods for controlling regeneration of a particulate filter positioned downstream of an engine in a vehicle are provided herein. One exemplary method includes, during combusting engine conditions, directing exhaust from the engine to a three-way catalyst and then to the particulate filter, and during non-combusting engine conditions and while the vehicle is in motion, directing fresh ram-air to between the particulate filter and the catalyst to regenerate the particulate filter. Thus, vehicle motion may be used to introduce the ram-air.

Abstract: Systems and methods for controlling regeneration of a particulate filter downstream of an engine having a plurality of cylinders are provided. One exemplary method includes, during first conditions, spinning down the engine to non-combusting engine rest, and regenerating the particulate filter at least during engine rest. The method also includes, during second conditions, regenerating the particulate filter during combustion of at least one cylinder of the engine. By regenerating the particulate filter during engine shutdown and/or engine rest in some conditions, it is possible to reduce engine running regeneration, which can thereby lead to reduced engine running emissions.

Abstract: Provided is an exhaust emission control device for an internal combustion engine capable of preventing NOx purification performance from degrading according to the operating condition. The exhaust emission control device comprises a NOx purification catalyst, a catalytic converter for continuously reducing the NOx in the exhaust emissions, a fuel reformer for reforming fuel to manufacture a reformed gas and supplying the reformed gas as the reducing gas from the upstream side of the NOx purification catalyst and the catalytic converter of the exhaust pipe, an operating condition detecting means for detecting the operating condition of an engine, and an enriching means for enriching the exhaust air-fuel ratio. The enriching means enriches the exhaust air-fuel ratio by supplying the reducing gas into the exhaust pipe by using the fuel reformer when the operating condition detected by the operating condition detecting means is a high-load operating condition.

Abstract: A regeneration system includes a particulate matter (PM) filter loading module that determines a current soot loading level of a PM filter. A PM filter temperature module determines a temperature of the PM filter. An exhaust flow rate module determines an exhaust flow rate of the PM filter. A control module deactivates an air pump of an air pump circuit and operates an engine within a predetermined range of stoichiometry based on the current soot loading, the temperature and the exhaust flow rate.

Abstract: A variety of embodiments of exhaust systems for engines including small off-road engines, and related methods of operation, are disclosed. In at least some embodiments, the exhaust system includes a first conduit that receives exhaust emissions from a first engine cylinder, and a second conduit that communicates air to a first port on the first conduit. The air mixes with the exhaust emissions within the first conduit so as to produce a chemical reaction, and a level of at least one undesirable component of the exhaust emissions is reduced. Further, the exhaust system does not include any catalytic converter. In some embodiments, the exhaust system further comprises a crankcase ventilation system.

Abstract: A secondary air supply system includes a secondary air supply device that supplies secondary air to the upstream side of an exhaust emission control device installed in an exhaust system of an internal combustion engine, and an ECU that estimates the secondary air temperature, and estimates the exhaust gas temperature after supply of secondary air, based on the result of estimation. The ECU starts or inhibits supply of secondary air by the secondary air supply device, depending on the result of estimation of the exhaust gas temperature. It is thus possible to prevent discharge of unburned fuel components, by estimating the exhaust gas temperature after supply of secondary air in view of the secondary air temperature.

Abstract: Systems and methods for controlling regeneration of a particulate filter downstream of an engine in a vehicle are provided herein. One exemplary method includes, during first engine shutdown conditions, increasing excess oxygen to the particulate filter, and regenerating the particulate filter at least during a portion of engine shutdown. The method further includes during second engine shutdown conditions, decreasing the excess oxygen to the particulate filter at least during a portion of engine shutdown.

Abstract: Systems and methods for controlling regeneration of a particulate filter downstream of an engine coupled to an energy conversion device are provided herein. One exemplary method includes, during first engine shutdown conditions, increasing excess oxygen to the particulate filter by spinning the engine with the energy conversion device, and regenerating the particulate filter. The method also includes, during second engine shutdown conditions, decreasing the excess oxygen to the particulate filter.

Abstract: Systems and methods for controlling regeneration of a particulate filter downstream of an engine in a vehicle are provided herein. One exemplary method includes, during an engine shutdown, increasing a throttle opening and regenerating a particulate filter downstream of a three-way catalyst. The method also includes, during an engine start following an engine shutdown, setting one or more engine parameters based on whether the particulate filter was regenerated during a last engine shutdown before the engine start.

Abstract: A secondary air supply device that increases a supply amount of secondary air is provided in a straddle-type vehicle and includes a plurality of secondary air supply pipes respectively communicated with an exhaust passage of an engine and reed valves. The plurality of reed valves are arranged to be spaced apart in the vehicle width direction so as to increase the supply amount of secondary air.

Abstract: A method for regenerating a particulate filter of an internal-combustion engine, provides for air to be supplied into the exhaust gas pipe upstream of the particulate filter in order to perform post-combustion in the exhaust gas pipe. The method provides for fuel to be supplied to the cylinders of the internal-combustion engine by means of a high-pressure pumping unit, and for fuel to be supplied into the exhaust pipe upstream of the particulate filter by means of the high-pressure pumping unit.

Abstract: The present invention provides a mixing device (1) for mixing urea with a gas, said urea being preferably dissolved in a fluid preferably water and said gas being preferably air. The mixing device comprises preferably a urea inlet (10) and a gas inlet (12) for feeding respectively urea and the gas into a mixing chamber (20) of the mixing device (4), and an outlet (14) for outlet of the mix of urea and gas from the mixing chamber (20), these inlets (10,12) and outlet (14) may preferably have a stream wise extension and runs preferably into the mixing chamber (20) and the outlet (14) originates preferably from the mixing chamber (20). Preferably, at least the gas inlet (12) for feeding air into the mixing chamber is designed so that depositing of urea crystals on selected surfaces of the said inlet is substantially (typically in the sense that deposited crystals does not clog the inlet) or totally avoided.

Abstract: An object of the present invention is to prevent an excessive temperature rise of a precatalyst in the case where the precatalyst is provided in the exhaust passage upstream of an exhaust gas purification apparatus and has a heat capacity smaller than that of the exhaust gas purification apparatus, and reducing agent is added from a reducing agent addition valve toward an upstream end surface of the precatalyst. According to the present invention, the reducing agent addition valve is located in such a way that the reducing agent added through it reaches the precatalyst in a liquid state.

Abstract: An exhaust device for a vehicle, such as a motorcycle or scooter, includes an exhaust pipe and a muffler. A first end portion of the exhaust pipe is connectable to an engine of the vehicle. A second end portion of the exhaust pipe is located within the muffler. A secondary air induction pipe supplies air to the exhaust pipe and is connected to a portion of the exhaust pipe located within the muffler. Furthermore, at least the portion of the exhaust pipe to which the secondary air induction pipe is connected is linear. A purification tube member for purifying exhaust gas forms a portion of the second end portion of the exhaust pipe.

Abstract: An internal combustion engine capable of efficiently supplying air to an exhaust path even in a high load state. The internal combustion engine includes a convergent section, a divergent section, and a branch section. The branch section branches a shock wave, propagating in a downstream direction at a higher velocity than exhaust gas flowing into an exhaust path from a combustion chamber when an exhaust valve is opened, from a portion of the exhaust path which is upstream with respect to the divergent section, and propagates the shock wave back to the exhaust path. The exhaust gas is caused to pass the convergent section and to collide against the shock wave between the branch section and the divergent section so as to increase the pressure of the exhaust gas in the convergent section. Such exhaust gas is caused to pass the divergent section to generate a new shock wave.

Abstract: A system for controlling the temperature of an exhaust stream includes a main exhaust passageway adapted to receive the exhaust stream from an engine. A bypass passage includes an inlet and an outlet in communication with the main exhaust passageway. The outlet is located downstream from the inlet. A burner is positioned within the bypass passage for treating the exhaust passing through the bypass passage. A valve is positioned within the main exhaust passageway downstream from the inlet and upstream from the outlet. The valve is operable to vary the exhaust flow through the burner. A controller selectively operates the burner to maintain a desired exhaust temperature downstream of the outlet.

Abstract: An exhaust gas cooling apparatus and method for cooling an exhaust gas is provided. The exhaust cooling apparatus has a first fluid conduit and a variable nozzle extending from the first fluid conduit. The variable nozzle being disposed in an inlet end of a second fluid conduit, wherein the variable nozzle has at least two dissimilar materials adjacent to each other and a fluid inlet opening is located between an outer periphery of the variable nozzle and an inner surface of the inlet end of the second fluid conduit. The at least two dissimilar materials vary the size of an opening of the variable nozzle by moving toward or away from a center line of the first fluid conduit in response to a temperature of an exhaust gas flowing through the first fluid conduit.

Abstract: A flammable-gas led-out pipe (5) has a terminal end portion (5a) disposed in an exhaust-gas route (7) and a metal cylinder (10) is arranged at the terminal end portion (5a) of the flammable-gas led-out pipe (5). An oxidation catalyst (8) is disposed within the metal cylinder (10). On an upstream side of the oxidation catalyst (8), an air-supply passage (12) is opened to provide an outlet (12a) and the flammable gas (4) merges with supplied air (13). The flammable gas (4) is burnt with the oxidation catalyst (8) to produce catalyst-combustion heat, which is radiated from an outer peripheral surface of the metal cylinder (10) into the exhaust gas (9) in the exhaust-gas route (7) and the exhaust gas (9) heated by this heat-radiation is mixed with the flammable gas (4) that has passed through the oxidation catalyst (8).

Abstract: A vehicle can include an engine, an air cleaner for supplying air taken in by the engine, an exhaust passage for exhausting exhaust gas of the engine, and a secondary air passage for connecting the air cleaner to the exhaust passage and for supplying secondary air to the exhaust passage. A one-way valve can be disposed in the secondary air passage. A resonator portion can be interposed between the air cleaner and the one-way valve. The resonator portion can branch from the secondary air passage and can include a closed space. A water drain portion can be disposed in the closed space of the resonator portion.

Abstract: An exhaust gas purifying apparatus for an internal combustion engine is provided to desorb predetermined components contained in exhaust gas from an adsorption device for adsorbing the components and to purify the desorbed components, even during the stop of the internal combustion engine. A main exhaust passage and a bypass passage bypassing the main exhaust passage are provided. An exhaust switching valve is capable of switching a flow target into the exhaust gas flows between the main exhaust passage and the bypass passage. An adsorbent for adsorbing the predetermined components is provided in the bypass passage. An underfloor catalyst including a catalyst with a heater is provided at a downstream side of the bypass passage in the main exhaust passage. A pump and a heater are provided in an air supply passage which branches from the bypass passage at an upstream portion of the adsorbent.

Abstract: An exhaust system for an internal combustion engine includes an air injection port in a designated region of an exhaust conduit having a converging-then-diverging nozzle providing increased exhaust gas flow velocity and decreased exhaust gas pressure. In another embodiment, an injection air conduit is connected between an alternator blower and the engine exhaust conduit to supply injection air to the latter.

Abstract: An exhaust system for an engine is disclosed. The exhaust system may have a NOx reducer located to receive exhaust from the engine, and a bypass circuit configured to selectively pass supercharged air to the NOx reducer. The exhaust system may also have a valve disposed within the bypass circuit to regulate the flow of supercharged air, and a controller in communication with the valve. The controller may be configured to move the valve to pass the supercharged air and cool the exhaust received by the NOx reducer. The controller may also be configured to move the valve to reduce the passing of the supercharged air and remove sulfur compounds from the NOx reducer.

Abstract: Various systems and methods are described for controlling a NOx sensor coupled to an engine exhaust system in a motor vehicle. One example method comprises generating an offset of the sensor based on an ambient air flow drawn into the exhaust system, the ambient air flow having circumvented cylinders of the engine, and adjusting an output of the sensor based on the generated offset.

Abstract: The invention relates to a control method for increasing the exhaust gas temperature of an internal combustion engine by increasing the exhaust back-pressure, yet maintaining an exhaust gas recirculation rate. Further, the fuel injection quantity of a main injection into the engine is increased. In this way, it is possible to increase the temperature of the exhaust gas and avoid engine oil dilution due to retarded post-injections.

Abstract: An abnormality diagnosis apparatus for diagnosing abnormality of a secondary air supply assembly includes an abnormality diagnosing unit, an air-fuel ratio learning/correcting unit, a learning degree computing unit, and a prohibition unit. The abnormality diagnosing unit diagnoses abnormality of the secondary air supply assembly based on an output of the air-fuel ratio detecting unit. The air-fuel ratio learning/correcting unit learns variation of an air-fuel ratio control system of the engine and corrects variation of an air-fuel ratio based on a result of learning the variation of the air-fuel ratio control system. The learning degree computing unit computes a learning degree, by which the air-fuel ratio learning/correcting unit learns the variation of the air-fuel ratio control system. The prohibition unit prohibits the abnormality diagnosis or makes a diagnostic result invalid when the learning degree is equal to or less than a predetermined value.

Abstract: An exhaust gas purification system includes: a catalyst (3) provided in an exhaust gas passage of an internal combustion engine (1) and having a carrier containing a basic oxide and platinum carried on the carrier; a catalyst (4) for purifying NOx; and oxygen supply means (2).

Abstract: An engine compartment arrangement for an agricultural harvester comprises an engine (10), a diesel particulate filter (12) coupled to the engine (10) to receive and filter hot exhaust gases therefrom, a fan (14), a radiator (16) disposed in a cooling airflow path in front of the fan (14) and coupled to the engine (10) to cool said engine (10), a cleaning air duct (18) having a first end (20) disposed immediately behind the fan (14) to receive a portion of the air ejected from the fan (14), and having a second end (22) disposed adjacent to the top of the diesel particulate filter (12) to exhaust a jet of the ejected air at a sufficient speed and in sufficient volume across the top surface (24) of the diesel particular filter (12) to prevent an accumulation of agricultural debris on top of the diesel particulate filter (12).

Abstract: Various systems and method are described for controlling an engine having an exhaust system which includes a particulate filter. One example method comprises, after shutting down the engine and spinning down the engine to rest, operating a vacuum pump to draw fresh air through the exhaust system to an intake system, and regenerating at least a portion of the particulate filter during the engine rest.