Abstract: A power system is provided having a power source, a first power source section with a first intake passage and a first exhaust passage, a second power source section with a second intake passage and a second exhaust passage, and an oxygen separator. The second intake passage may be fluidly isolated from the first intake passage.

Abstract: A method for rapidly heating an emission control device in an engine exhaust uses excess air added to the exhaust via an air introduction device. After an engine cold start, the engine is operated to raise exhaust manifold temperature to a first predetermined value by operating the engine with a lean air-fuel ratio and retarded ignition timing. Once the exhaust manifold reaches the predetermined temperature value, the engine is switched to operate rich and air is added via the air introduction device. The added air and rich exhaust gas burn in the exhaust, thereby generating heat and raising catalyst temperature even more rapidly. The rich operation and excess air are continued until either engine airflow increases beyond a pre-selected value, or the emission control device reaches a desired temperature value. After the emission control device reaches the desired temperature, the engine is operated substantially around stoichiometry.

Abstract: Disclosed herein is a method and apparatus for reducing exhaust gases in an initial cold start period, in which a main catalyst unit is connected to an engine through an exhaust pipe, including the steps of receiving signals for stopping engine operation from an engine, and removing engine exhaust gases remaining in an exhaust pipe located at an inlet of a main catalyst unit.

Abstract: A secondary air pipe is connected on the upstream side from catalyst in an exhaust pipe, and a secondary air pump is provided at an upstream portion of the secondary air pipe. An opening/closing valve for opening/closing the secondary air pipe is provided on the downstream side from the secondary air pump. A pressure sensor for detecting pressure within pipe is provided between the secondary air pump and the opening/closing valve. An ECU calculates a secondary airflow rate based upon difference pressure between both secondary air supply pressure which is detected by the pressure sensor when the opening/closing valve is opened under such a condition that the secondary air pump is operated, and also, shutoff pressure which is detected by the pressure sensor when the opening/closing valve is closed.

Abstract: The invention provides a process and system for purification of an exhaust gas stream from a combustion engine containing hydrocarbons, soot, carbon monoxide and sulphur dioxide. The process comprises the steps of oxidising the hydrocarbons and part of the soot in a first reactor in the presence of a first catalyst active in oxidising hydrocarbons and soot without oxidising sulphur dioxide and forming a partly purified exhaust gas stream, of cooling of the partly purified exhaust gas stream, of converting the carbon monoxide of the partly purified exhaust gas stream in a second reactor in presence of a second catalyst active in oxidising carbon monoxide without oxidising sulphur dioxide and of withdrawing a purified exhaust gas stream.

Abstract: A muffler device with catalysts for improving purifying exhaust gas of nitrogen oxides within a motorcycle exhaust pipe comprises a muffler divided into three chambers, a first chamber, a second chamber, and a third chamber; a front exhaust pipe; a front reduction catalyst; a rear exhaust pipe provided with a secondary air inlet behind the reduction catalyst for introducing secondary air therein. Thereby, the exhaust gas from an engine with air-to-fuel ratio less than or equal to 14.7 will firstly pass the reduction catalyst to have its nitrogen oxides (NOX) effectively inverted into nitrogen (N2) and oxygen (O2), and then secondary air will be added to the exhaust gas so as to increase its air-to-fuel ratio to larger than 14.7, and finally the exhaust gas will pass the oxidation catalyst to have its carbon monoxide (CO) and hydrocarbons (HC) effectively inverted into carbon dioxide (CO2) and water (H2O).

Abstract: A secondary air control system supplies secondary air to the upstream of a catalyst purifying exhaust gas in an exhaust passage of an engine. A diagnostic device includes a secondary air detecting means that detects a secondary air information related to pressure of secondary air. An abnormality diagnostic means performs an abnormality diagnostic operation of the secondary air control system in accordance with the secondary air information. A voltage detecting means that detects a power source voltage information related to power source voltage supplied to the secondary air control system. An evaluating condition correcting means that corrects an evaluating condition, which is used for evaluating abnormality in the secondary air control system in accordance with a power source voltage information.

Abstract: In a secondary air delivery device for an internal combustion engine comprising a secondary air charger with a compressor and a turbine which is driven by the vacuum generated in the engine intake duct and which drives the compressor that delivers secondary air to the engine exhaust duct, wherein the engine intake air duct includes an air filter for filtering the air supplied to the engine, a separate air filter structure is provided for filtering the air supplied to the compressor and to the turbine which air filter structure is accommodated in the housing of the secondary air charger.

Abstract: The present invention relates to an arrangement for cooling an exhaust system of a vehicle having an internal combustion engine. The arrangement includes a controller for detecting an elevated temperature condition of the exhaust system, such as a so called hot soak condition, as well as detecting a predetermined engine operating status, such as either of an engine shutdown, a stopped or an idling status. A secondary air injection system may then be actuated to inject ambient air into the exhaust system thereby cooling said exhaust system.

Abstract: A diesel exhaust gas system includes a diesel particulate filter (DPF), a trap for nitrogen oxides (LNT), a hydrocarbon catalytic reformer for generating reformate, and an air supply. A method for controlling the rate of burn of soot in a DPF limits the oxygen percentage in the exhaust to about 6%. The LNT may be located ahead of the DPF in the exhaust line. Reformate is directed with exhaust through the LNT. The second flow of air cools the exhaust gas and thereby prevents overheating of the DPF substrate. The DPF also may be located ahead of the LNT. Reformate is controllably combusted by the second air flow in the DPF, reducing the oxygen percentage to about 6%, thus limiting the rate at which soot in the DPF can burn and thereby preventing overheating of the DPF substrate.

Abstract: The invention relates to an internal combustion engine which has charge-air supercharging by means of an exhaust-gas turbocharger and secondary air injection, the flow path of which is selected in such a way that the quantity of secondary air injected has an influence on the rotational speed of the turbocharger. By monitoring the rotational speed of the turbocharger, an increase in the rotational speed caused by the secondary air injection is determined, and the quantity of secondary air injected is worked out from the increase in rotational speed. This has the advantage that there is no need for complex temperature-measuring methods as have hitherto been employed. Rotational speed measurement can be carried out contactlessly and with absolutely no wear in particular by means of inductive rotational-speed sensors. Moreover, these inductive rotational-speed sensors can be miniaturized and produced at extremely low cost.

Abstract: There is provided a device for supplying secondary air, which comprises a secondary air passage for supplying secondary air, to an exhaust passage of an engine, upstream of an exhaust purification device provided in the exhaust passage, a pump provided in the secondary air passage for supplying a secondary air, a battery used for driving the pump, at least one opening-closing device for opening and closing the secondary air passage, and a pressure sensor provided between the pump and the opening-closing device for detecting a pressure in the secondary air passage. A malfunction of at least one of the pump and the opening-closing device is detected on the basis of at least one of the pressures detected when the secondary air passage is opens and when the secondary air passage is closed.

Abstract: A method for operating an internal combustion engine by introducing air, in which the air is conducted into the induction region of the internal combustion engine following shutoff of the internal combustion engine. If necessary, the intake valves and the exhaust valves of at least one cylinder are moved into a position in which at least one intake valve and one exhaust valve of a combustion chamber of the internal combustion engine are open simultaneously. The method may be used in for an internal combustion engine having an electric turbocharger for the introduction of air.

Abstract: A working machine includes an engine compartment, an engine hood, an internal combustion engine arranged in the engine compartment and an exhaust system, which extends from the engine out of the engine compartment via the engine hood. The exhaust system is provided with an air intake for admitting air from the engine compartment into the exhaust system and entraining the air together with the exhaust gases. The air intake includes an air baffle element, which leads the air into an essentially central area in an outlet duct, in which the exhaust gases are led out, in such a way that the air is entrained out of the engine compartment by the exhaust gases through an ejector effect which the exhaust gases exert on the air in the outlet duct.

Abstract: In a diesel engine equipped with a catalytic HC reformer for injecting reformate into the engine exhaust stream to reductively regenerate one or more emissions control devices including but not limited to a lean nitrogen trap, a combustor is disposed in the exhaust stream downstream of the LNT, and preferably downstream of all regenerable emissions control devices, to burn any residual HC, H2, or CO in the tailpipe exhaust gases. Thus only breakthrough amounts of these species are combusted. Preferably, the combustor is operated on an appropriate schedule governed by the operating schedule of the reformer. To assure combustion when the oxygen concentration of the exhaust falls below the reformate combustion limit of approximately 6%, make-up air is ported to the combustor either by diverting a portion of the reformer system air or by diverting excess turbocharger boost air from the engine air intake system.

Abstract: In a secondary air supplying structure of an internal combustion engine, extending portions protruding upward are arranged in the number corresponding to the number of cylinders. Extending portions are each provided with a secondary air distribution path. To a surface of extending portion to which secondary air supplying pipe abuts, a seating face that conforms to the outer shape of secondary air supplying pipe is formed. Secondary air distributing path is arranged to be inclined downwardly from secondary air supplying pipe side toward the cylinder exhaust system of cylinder head. Thus, it is possible to provide the secondary air supplying structure of an internal combustion engine that can attain an improvement in the strength of the secondary air supplying path, reduction of the space, rust prevention, reduced costs, reduced weight, simplified structure, and prevention of thermal damage to other components.

Abstract: The invention relates to a method for monitoring a control unit of an internal combustion engine, according to which a variable, which characterises the initial parameter of a lambda regulation system, is monitored for a deviation from a predefined threshold value. An error response takes place in accordance with the deviation that has been determined.

Abstract: Apparatus and a method for controlling gas flow into a combustion engine exhaust gas filter e.g., to control filter temperatures during filter regeneration, comprising providing a fluidic exhaust stream diverter proximate to and centrally of the inlet face of the filter and activating the fluidic diverter to divert exhaust gas flow away from central filter portions toward peripheral filter portions.

Abstract: A method for rapidly heating an emission control device in an engine exhaust uses excess air added to the exhaust via an air introduction device. After an engine cold start, the engine is operated to raise exhaust manifold temperature to a first predetermined value by operating the engine with a lean air-fuel ratio and retarded ignition timing. Once the exhaust manifold reaches the predetermined temperature value, the engine is switched to operate rich and air is added via the air introduction device. The added air and rich exhaust gas burn in the exhaust, thereby generating heat and raising catalyst temperature even more rapidly. The rich operation and excess air are continued until either engine airflow increases beyond a pre-selected value, or the emission control device reaches a desired temperature value. After the emission control device reaches the desired temperature, the engine is operated substantially around stoichiometry.

Abstract: A secondary air pressure detecting apparatus includes a solenoid valve and a pressure sensor. The solenoid valve defines a secondary air passage that introduces secondary air from the air pump into the exhaust system of an engine. The solenoid valve opens and closes the secondary air passage. The pressure sensor is integrally mounted to the solenoid valve to detect pressure of secondary air in the solenoid valve. The solenoid valve includes a coil assembly and magnetic members. The coil assembly includes a solenoid coil that generates magnetic force when the solenoid coil is energized. The magnetic members construct a magnetic circuit with the solenoid coil. The magnetic circuit is arranged outside of the secondary air passage. The pressure sensor is arranged on an opposite side of the secondary air passage with respect to the magnetic circuit.

Abstract: The invention relates to a method and an arrangement for controlling a drive unit (1), especially of a vehicle, having a combustion engine (5). The method and arrangement make possible a correct charge control when utilizing a secondary air charger (10) as well as make possible a diagnosis of the secondary air charger (10). Secondary air is blown into an exhaust-gas system (15) of the combustion engine (5) via the secondary air charger (10). The secondary air charger (10) is driven by a pressure drop across an actuating element (20) for adjusting an air supply to the engine (5). The actuating element (20) is driven for adjusting an air supply to the engine (5) corrected in dependence upon an air mass flow driving a turbine (25) of the secondary air charger (10).

Abstract: In an arrangement for reducing exhaust emissions and utilizing the throttling energy of an internal combustion engine, a compressor and a generator are operatively connected to a turbine by which the intake air flow is controlled while transferring the throttling energy recuperated by the turbine to the compressor and the generator and, in the engine start-up phase, the compressor supplies fresh air to an engine air intake duct, the intake air flow volume being controlled by the energy withdrawn from the turbine via the compressor and the generator thus eliminating the need for a throttle valve in the fresh air intake line.

Abstract: Hydrogen-rich reformate gas is produced by a fuel reformer (2) from fuel vapor containing hydrocarbon, which is produced by a fuel vaporizer (6), by means of a partial oxidation reaction and a steam reforming reaction. A fuel injector (8, 9) supplies fuel to the fuel vaporizer (6), and an air injector (8a) supplies air to the fuel vaporizer (6). A glow plug (13) partially oxidizes the air-fuel mixture inside the fuel vaporizer (6). By controlling the air supply amount in relation to the fuel supply amount to obtain an excess air factor corresponding to a predetermined rich air-fuel ratio, a part of the air-fuel mixture in the fuel vaporizer (6) is partially oxidized, and the remaining fuel vapor is heated by the oxidation heat. As a result, the partial oxidation reaction and steam reforming reaction in the fuel reformer (2) are performed with a favorable balance.

Abstract: The invention relates to a method and an arrangement for monitoring the operability of a secondary air system of an internal combustion engine having an exhaust-gas system. The secondary air system includes a secondary air pump. In the method and arrangement, a signal is determined which characterizes the secondary air flow. In the method, at least one signal of at least one operating characteristic variable of the secondary air pump is determined during the determination of the signal characterizing the secondary air flow and a conclusion is drawn as to a fault in the secondary air system when the signal of the at least one operating characteristic variable lies outside of a pregiven interval. The at least one signal of at least one operating characteristic variable is determined in dependence upon the operating state of the engine. This signal is determined from a signal for the pump current of an electrically operated secondary air pump.

Abstract: In a secondary air supply system, each of two branch portions of a secondary air supply pipe that is divided from a joint portion is provided with an air control valve, and the joint portion is provided with a pressure sensor and an auxiliary air control valve. The air control valves are opened at different timings such that pressure fluctuations in the joint portion upon opening of the firstly and the secondly opened air control valves are measured. An abnormality diagnosis is performed with respect to those two air control valves based on combinations of the aforementioned two pressure fluctuations.

Abstract: When a specified air-fuel ratio F/B control condition is established during supply of a secondary air provided, an air-fuel ratio F/B control is executed, and at this time, an initial value of a target air-fuel ratio is set to a before-catalyst air-fuel ratio detected by an A/F (air-fuel ratio) sensor. The target air-fuel ratio subsequent to this is gradually changed from the initial value to a specified air-fuel ratio. By this, the initial value of the target air-fuel ratio can be suitably set at a start time of execution of the air-fuel ratio F/B control during the supply of the secondary air. The target air-fuel ratio subsequent to this is gradually changed to a stoichiometric air-fuel ratio, so that a change in engine rotation speed is suppressed and the drivability can be improved.

Abstract: In one example, a system for an engine having an intake system and an exhaust system is described. The system comprises: an airflow sensor coupled to the intake system; an air pump having at least an inlet side and an outlet side, said inlet side having a first coupling to the intake system downstream of said airflow sensor, said outlet side having a second coupling to the exhaust system; and a controller coupled to the engine, said controller, during operation, identifying whether degradation has occurred to at least one of said first and second couplings, and providing an indication of said identified degradation. Various other examples are also disclosed.

Abstract: In an exhaust path, a HC trapping material which traps HC contained in exhaust gas temporarily, a H2O trap which traps H2O contained in exhaust gas and a CO oxidation catalyst are arranged in this order from the upstream side, wherein the H2O trap is disposed just upstream of and close to the CO oxidation catalyst. H2O and HC which are components disturbing the activity of the CO oxidation catalyst can be removed efficiently and the adsorption heat and condensation heat of H2O can be efficiently utilized to raise the temperature of the CO oxidation catalyst so that early activation of the CO oxidation catalyst is accomplished just after an engine starts.

Abstract: The invention proposes a system (16) for treating the exhaust gases (G) of a motor vehicle combustion engine (10), particularly a lean-burn diesel engine or engine, comprising a burnt gas (G) exhaust circuit (14), of the type in which the exhaust circuit (14) comprises a burnt gas (G) ionization system (22), characterized in that the exhaust circuit (14) comprises an ionized air injection system (24) upstream and/or downstream of the burnt gas (G) ionization system (22).

Abstract: An internal combustion engine is supplied with reformate from a hydrocarbon reformer at engine start-up and during engine warm-up. The reformate fuel mixture is fuel-lean at start-up to ensure that all the fuel is burned while the exhaust converter is thermally non-functional. Shortly after start-up, the mixture is changed to be fuel-rich, providing unburned reformate fuel in the exhaust stream. During start-up and warm-up, the output of an air pump is controllably divided between the reformer (primary air) and the engine exhaust system (secondary air). Unburned reformate from the engine and secondary air from the air pump ignite and thereby rapidly heat the converter. Gasoline or diesel fueling of the engine by fuel injection is preferably delayed until the engine and the converter both reach operating temperatures, whereupon the engine is fueled by fuel injection and further reforming is terminated.

Abstract: A method for operating an electro motor-driven secondary air pump which is provided for injecting secondary air into the exhaust system of an internal combustion engine. The secondary air pump is operated in a clocked manner. The induced voltage at the electro motor of the secondary air pump, measurable during the turn-off time of the clocked operation, is used for diagnosing as well as for controlling the speed of the secondary air pump. The diagnosis is carried out based on the evaluation of a parameter (difference quotient, differential quotient) of the induced voltage. The induced voltage is instantaneously a measure for the secondary air pump's actual speed value, so that a separate detection of the actual speed value is omitted.

Abstract: An engine control system and method maintains an optimum exhaust fuel to air ratio in an internal combustion engine. A secondary air injection (SAI) pressure is measured in an SAI system. The SAI pressure measurement is converted into an SAI flow value. A fuel compensation value is obtained based on the SAI flow value. Fuel delivery is compensated to the engine based on the fuel compensation value. In a second embodiment, the fuel compensation value is obtained based on the SAI pressure measurement. Fuel delivery is compensated to the engine based on the fuel compensation value. In a third embodiment, a primary flow value is calculated at an air intake of the engine. A fuel compensation value is calculated based on the SAI flow and primary flow values. Fuel delivery to the engine is compensated based on the fuel compensation value.

Abstract: A failure diagnosis apparatus for secondary air supplier according to the present invention determines a failure of a secondary air supplier based on pressure and pressure pulsation in a secondary air supply path. A failure diagnosis is made by determining the presence or absence of pressure pulsation in the secondary air supply path based on a determination threshold, and in the present invention the determination threshold is varied according to a pressure value in the secondary air supply path (a smoothed value or an average value of measured pressure). This permits the apparatus to make an accurate failure diagnosis, while eliminating pressure pulsations except for that due to exhaust pulsation (e.g., that due to noise of the pressure sensor and that caused by surging of an air pump).

Abstract: A secondary air supplying apparatus of the present invention comprises a secondary air supplying device for supplying secondary air to upstream of an emission purifying device in an exhaust system of an internal combustion engine, a coolant temperature sensor for detecting a temperature of a coolant for the engine, an intake air temperature sensor for detecting a temperature of intake air, a supply controller for actuating the secondary air supplying device in accordance with a predetermined secondary air supply condition, and a summing unit for summing an actuation period of the secondary air supplying device and storing a sum. The supply controller stops the secondary air supply by the secondary air supplying device when the sum stored by the summing unit reaches a predetermined upper limit.

Abstract: In a secondary air injection system, MOSFETs control supply of electric current to an air pump and to a motor for driving an electromagnetic valve and to an electromagnetic coil to introduce secondary air into an exhaust gas passage upstream of a catalyst for purifying the exhaust gas of an internal combustion engine. Gate drive circuits control the MOSFETs based on an instruction from an ECU via input signal processing circuits. Abnormal conditions in the operation for controlling the air pump and the electromagnetic valve are detected, and, when an abnormal condition is detected, forcibly turn the MOSFETs off to interrupt the current to the motor and to the electromagnetic coil. A diagnosing circuit sends to the ECU diagnosis signals representing the state of controlling the load.

Abstract: A method and a device for implementing a method for ascertaining the load condition with an exhaust-gas component of a component arranged in an exhaust-gas region of an internal combustion engine is provided in which an increase in the exhaust-mass flow of the internal combustion engine and a detection of a pressure change in the exhaust-gas region in front of the component is specified. The load condition of the component is determined from the pressure change.

Abstract: In order to improve the decrease of the catalytic action and the deterioration of the exhaust purification performance, a catalyst installed in the exhaust pipe of an engine and a secondary air pump for supplying secondary air into the exhaust pipe are provided, and the secondary air pump is operated even after the engine has stopped.

Abstract: A secondary air supply apparatus controls emissions from an engine through secondary combustion of combustible matters in exhaust gas accomplished by supplying air to an exhaust pipe upstream of an emission control device. A pressure behavior pattern is determined from a pressure value detected by a pressure sensor disposed between an air pump and an open-close valve, and a pressure variation value. The secondary air supply apparatus determines operational states of the air pump and the open-close valve based on variations of the pressure behavior pattern at the time of a secondary air supply control and at the time of a secondary air stop control.

Abstract: A diesel particulate matter reduction system includes a diesel particulate filter (DPF), an electric power supply device, a heater, an air blower, and a control unit. The DPF is configured to capture particulate matter of exhaust gas. The heater is configured to be operated by electric power supplied by the electric power supply device to heat the DPF. The air blower is configured to be operated by electric power supplied by the electric power supply device and provides air to the DPF. The control unit controls operations of the heater and the air blower.

Abstract: An upstream-side catalyst is arranged in an exhaust passage and a downstream-side catalyst is arranged in the exhaust passage downstream of the upstream-side catalyst. An air-fuel ratio sensor is attached for detecting the air-fuel ratio in the exhaust passage between the upstream-side catalyst and downstream-side catalyst. A representative upstream-side stored oxygen value OXU is calculated based on whether the control state of the engine is the “slight rich” control, “slight lean” control, fuel increase correction, or engine fuel cut and a representative downstream-side stored oxygen value OXD is calculated based on the engine control state and the output of the air-fuel ratio sensor.

Abstract: An exhaust purification system for use with diesel or other compression ignited systems to remove particulate and gaseous pollutants from the exhaust. The system includes a catalytic converter assembly that heats the exhaust to a level sufficient to incinerate particulate pollutants in the exhaust prior to the pollutants contacting the catalytic element and a plurality of gas cooling elements communicating with the exhaust outlet in the catalytic converter assembly for reducing the temperature of the exhaust passing from that assembly to about 100° F. whereupon the cooled exhaust is directed back to the engine for further combustion.

Abstract: There are provided a particulate filter and a manual regeneration switch. When the manual regeneration switch is operated and the vehicle is in a stop state, the engine speed is adjusted to a first target higher than a normal idle speed to regenerate the filter. Meanwhile, when the vehicle changes from its stop state to its driving state, the engine speed is adjusted to a second target higher than the normal idle speed but lower than the first target in the event that the temperature of the filter is high, while the engine speed is adjusted to the normal idle speed in the event that the temperature of the filter is low. Accordingly, deterioration of the durability of the filter due to its rapid temperature increasing can be suppressed, avoiding disadvantages of fuel efficiency and vehicle start feeling.

Abstract: In the disclosed secondary air supply system, an on-off valve (13) is driven by the discharge pressure of an air pump (12). A diaphragm chamber (44) is arranged in the neighborhood of a discharge outlet (54), and a part of the discharge air flows directly into the diaphragm chamber (44). Thus, the on-off valve (13) is positively operated even at high places with low atmospheric pressure and has a fast open/close response. As an electromagnetic actuator is not used to drive the on-off valve (13), the voltage supplied to the air pump (12) (DC motor (29)) does not drop inconveniently, and at the same time, the cost is reduced. Further, the number of the lead wires (65) is reduced.

Abstract: A burner for use in the emissions system of a lean burn internal combustion engine. The burner has a special burner head that enhances atomization of the burner fuel. Its combustion chamber is designed to be submersed in the engine exhaust line so that engine exhaust flows over the outer surface of the combustion chamber, thereby providing efficient heat transfer.

Abstract: In an electrical multi-purpose valve for supplying secondary air into an exhaust system of an internal combustion engine, in which a power-actuated closing member controls a valve orifice in a passage between an inlet from an air supply line and an outlet to the exhaust system, a non-return valve is arranged downstream of the closing body in the direction of the flow of the air through the valve between the non-return valve and the valve outlet, and baffle devices are provided which deflect exhaust gas entering the valve from the outlet at least once by an angle of about 90°.

Abstract: An anomaly judgment apparatus for a secondary air supply system which includes a secondary air supply path for introducing secondary air into an exhaust path of an internal combustion engine and an open-close valve disposed in the secondary air supply path. The valve is opened and/or closed by drive force of negative pressure introduced from a portion of an intake path of the engine downstream of a throttle valve. The anomaly judgment apparatus includes an anomaly judgment section for judging whether or not the secondary air supply system is anomalous; a negative pressure judgment section for judging whether or not the negative pressure is secured to a degree required for the drive force to reliably open and/or close the open-close valve; and an anomaly judgment prohibition section for prohibiting judgment by the anomaly judgment section when the negative pressure is not secured to the required degree.

Abstract: An exhaust emission purification device comprises a sulfur component holding agent arranged on the exhaust path of an internal combustion engine for holding a sulfur component, a NOx holding agent arranged downstream of the sulfur component holding agent in the exhaust gas for holding NOx and the sulfur components when the air-fuel ratio of the exhaust gas flowing thereinto is lean, and a reducing agent adding unit for adding a reducing agent to the exhaust gas flowing into the NOx holding agent. The concentration of the sulfur component contained in the reducing agent added by the reducing agent adding unit is lower than the concentration of at least the sulfur component contained in the fuel supplied to the combustion chamber of the internal combustion engine. Thus, the sulfur poisoning of the exhaust emission purifier can be avoided while at the same time reducing the fuel consumption rate.

Abstract: A diagnostic system according to the present invention diagnoses system failure of a secondary air injection system. The secondary air injection system includes a pump that provides air to an exhaust system via a conduit and a valve that controls the flow of air through the conduit. A pressure sensor measures pressure in the conduit. A controller predicts pressure in the conduit during first, second and third operational phases of the secondary air injection system. The controller compares the measured pressure to the predicted pressure to evaluate operation of the secondary air injection system. During the first phase, the secondary air injection system is used to reduce vehicle emissions. During the second phase, the valve is shut while the pump is on. During the third phase, the pump is turned off while the valve is closed.

Abstract: A secondary air supply system includes an exhaust gas control catalyst which is provided in an exhaust system in an internal combustion engine, and which purifies a harmful component in exhaust gas; a secondary air supply device which supplies secondary air into the exhaust gas upstream of the exhaust gas control catalyst; a secondary air supply stop device which stops the secondary air supply performed by the secondary air supply device; a fuel supply device which supplies fuel to the internal combustion engine; a fuel amount increasing device which increases a fuel amount supplied to the internal combustion engine during the secondary air supply; and a fuel amount increase stop time delaying device which delays, by a predetermined delay period, a stop time at which the increase in the fuel amount caused by the fuel amount increasing device is stopped even when the secondary air supply is stopped.

Abstract: An apparatus for treating an exhaust gas stream from cold startup through continuous operating conditions of an internal combustion engine includes an oxidizing catalyst bed disposed in an exhaust pipe and a reducing catalyst bed disposed in the exhaust pipe downstream from the oxidizing catalyst bed. The oxidizing catalyst bed as one or more oxidizing catalysts and the reducing catalyst bed has one or more reducing catalysts. A method is provided for treating an exhaust gas stream both during cold start and during continuous operating conditions of an internal combustion engine by passing the stream through an oxidizing catalyst bed having one or more oxidizing catalysts at a light off temperature; a reducing catalyst bed having one or more reducing catalysts and providing hydrogen into the reducing catalyst bed to condition the reducing catalyst; and introducing hydrogen into the internal combustion engine during cold startup.