Abstract: The invention relates to a device and a method for producing an operating medium for a motor vehicle, especially for use in the exhaust gas post-treatment of the motor vehicle. According to said method, an operating medium is produced from an initial product and air using a catalyst device. Said initial product is heated and mixed with air and the heated mixture of initial product/air is fed to the catalyst device. A part of the initial product is converted to the gaseous phase by means of a preheating element and is entrained by a stream of air when leaving the preheating element, said stream of air leading to a combustion chamber. The method allows to efficiently produce an operating medium, especially a reducing agent for regenerating NOx storage catalysts.

Abstract: An exhaust purification catalyst warm-up system has an air pump that supplies air upstream from an exhaust purifying catalyst, disposed in an exhaust pipe of an internal combustion engine, the pump supplying air when the exhaust purifying catalyst is being warmed up. The exhaust purification catalyst warm-up system also has an atmospheric pressure sensor that detects the atmospheric pressure, wherein correction is performed so that the degree of fuel increase is smaller, the higher is the atmospheric pressure detected by the atmospheric pressure sensor.

Abstract: When starting an internal combustion engine from cold, after-burning of unburned HC in the exhaust gas within an exhaust passage is promoted by supplying secondary air into the exhaust passage upstream of a catalyst. At this time, the pressure within the exhaust passage is controlled by controlling the opening timing of an exhaust valve. Desirably, when the exhaust temperature has been elevated to a temperature at which it is possible to promote after-burning of the unburned HC in the exhaust gas within the exhaust passage, the opening timing of the exhaust valve is retarded.

Abstract: The present invention relates to a secondary air supply arrangement having an actuator operably connected to an air pump for creating air flow between an inlet and outlet of the air pump. A pulse width modulated controller is operably connected to the actuator for applying a pulse width modulated voltage to the actuator. The pulse width modulated controller controls the initial in-rush electric current when the actuator is activated.

Abstract: Clogging of an injection nozzle which supplies a reducing agent to the exhaust gas on an upstream side of a reduction catalyst in the exhaust gas passage is prevented, and the efficiency of NOx purification processing is improved. A reducing agent supply unit uses a detection signal of the exhaust gas temperature from a temperature detection device to set a supply quantity at or above a lower limit for cooling the interior of an injection nozzle to below the temperature at which urea water crystallizes, for the detected exhaust gas temperature, and supplies urea water to the injection nozzle at the set supply quantity. By such supply of urea water, the interior of the injection nozzle is cooled to below the temperature at which the urea water crystallizes. As a result, the urea water does not crystallize inside the injection nozzle, and clogging of the injection nozzle can be prevented.

Abstract: The present invention relates to an exhaust system for an internal combustion engine, in particular in a motor vehicle, with an exhaust line in which an oxidation catalyst is provided for treatment of the exhaust gases coming from the internal combustion engine. To be able to heat the oxidation catalyst more rapidly in a cold start of the internal combustion engine, a pre-oxidation unit may be provided in the exhaust line upstream from the oxidation catalyst and connected to a secondary fuel supply and adapted so that it partially oxidizes the secondary fuel supplied in combination with an oxidizer in a catalyst heating operation and the partially oxidized intermediate products are supplied to the oxidation catalyst for complete oxidation.

Abstract: A device for cooling a gas is provided. The device comprises an inlet having a first diameter, a mixing section downstream of the inlet and having a second diameter, and an opening in fluid communication with the mixing section and a source of air. The device is such that the second diameter is smaller than the first diameter and a vacuum is created for drawing in the air from the opening as gas passes from the inlet to the mixing section so that the air drawn into the mixing section mixes with the gas. A method for mixing two gases and an exhaust system are also provided.

Abstract: In a method for operating an exhaust-gas cleaning unit of a diesel engine including a particle filter and a nitrogen oxide storage device arranged upstream of the particle filter, wherein sulfur regeneration of the nitrogen oxide storage device is performed periodically at raised exhaust gas temperatures and, in certain phases, with a rich exhaust gas composition, and also soot regeneration of the particle filter is performed at raised exhaust gas temperatures with a lean exhaust gas composition, at least some of the sulfur regeneration and the soot regeneration phases are performed in a combined soot and sulfur regeneration phase, and for the sulfur regeneration, at least temporarily, a rich exhaust-gas composition with a temperature higher than the temperature of the lean exhaust gas composition is provided for the soot regeneration of the particle filter.

Abstract: Method and systems are provided for operating an engine having a hydrocarbon retaining system coupled to an engine exhaust and an engine intake. One example method comprises, during an engine cold start, routing exhaust gas to the hydrocarbon retaining system to store hydrocarbons in the hydrocarbon retaining system. The method further comprises, during a first purging condition where the exhaust gas is at a first temperature, purging the hydrocarbon retaining system with at least exhaust gas, and during a second purging condition where the exhaust gas is at a second temperature, said second temperature being higher than said first temperature, mixing the exhaust gas with an amount of fresh air to form a purging gas mixture, and purging the hydrocarbon retaining system with said purging gas mixture.

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: A method for operating a particulate filter situated in an exhaust gas area of an internal combustion engine and a device for carrying out the method are described. A measure of the particulate matter burn-off rate is detected for influencing and/or monitoring the particulate matter burn-off rate or for influencing and/or monitoring the particulate filter temperature. A secondary air flow supplied by a secondary air pump is blown into the exhaust gas area upstream from the particulate filter. The secondary air flow is determined as a function of the detected measure of the particulate matter burn-off rate. If necessary, the secondary air flow may be enriched by an oxygen flow or nitrogen flow supplied by an air separation unit. The method prevents the particulate filter from being damaged by an unacceptably high particulate matter burn-off rate or an unacceptably high particulate filter temperature.

Abstract: An ECU executes a program including a step (S102) of limiting the maximum opening amount of a throttle valve to TH (1) when failure has occurred in a pressure sensor (“YES” in step S100); a step (S202) of limiting the maximum opening amount to TH (2) when open failure has occurred in at least one of two vacuum pressure ASVs provided for banks of a V-type engine, and an electromagnetic ASV (“YES” in step S200); a step (S302) of limiting the maximum opening amount to TH (3) when open failure has occurred in both of the vacuum pressure ASVs (“YES” in step S300); a step (S402) of limiting the maximum opening amount to TH (4) when open failure has occurred in one of the vacuum pressure ASVs (“YES” in step S400); and a step (S502) of reducing the throttle valve opening amount TH to the limited maximum opening amount.

Abstract: A method of initiating regeneration of a filter assembly is disclosed. The method includes determining when regeneration of a filter assembly is to be initiated. The method also includes opening a first air valve configured to permit air flow to a regeneration assembly below a predetermined flow rate and at a sufficient flow rate to achieve ignition. The method further includes detecting ignition, and after ignition, opening a second air valve configured to supply air flow to the regeneration assembly above the predetermined flow rate and at a sufficient flow rate for regeneration.

Abstract: A cold-start control system includes an air pump control module that controls an air pump and an engine starting module that starts an engine. The air pump control module activates the air pump to supply oxygen to a catalytic converter based on a temperature of the catalytic converter. The engine starting module starts the engine based on the temperature of the catalytic converter.

Abstract: An engine system includes a diesel engine having an exhaust manifold connected to the diesel engine. An exhaust passage is connected to the exhaust manifold and a diesel particulate filter is disposed in the exhaust passage. An air intake passage is provided for supplying fresh air to the diesel engine. A bypass passage is connected between the air intake passage and the exhaust passage in a location downstream of the diesel particulate filter. The bypass passage includes a bypass control valve for opening and closing the bypass passage during a diesel particulate filter regeneration cycle when the vehicle is at low speed or idle.

Abstract: An exhaust gas purification system includes: at least two catalysts (1a, 1b) disposed in parallel with each other on an exhaust gas passage of an internal combustion engine (3) and having a carrier containing a basic oxide and platinum carried on the carrier; and oxygen supply means (2) for supplying oxygen to the catalysts (1a, 1b).

Abstract: Provided is an intake manifold pressure control apparatus, or vacuum pump, for a hybrid propulsion system. The vacuum pump is operable to evacuate the intake manifold of an internal combustion engine, thereby lowering the Manifold Absolute Pressure, or MAP, to a predetermined level to enable a quick restart of the internal combustion engine. This vacuum pump may also be used to evacuate hydrocarbons, or HCs, from within the intake system to prevent evaporative emissions from the intake manifold upon engine shutdown. In the preferred embodiment, the vacuum pump is operated by a motor that can simultaneously operate an auxiliary transmission oil pump. Additionally, the present invention provides a method of controlling the hybrid propulsion system to enable the manifold pressure control apparatus to lower the MAP value within the intake manifold as well as a method of evacuating HCs from the intake manifold upon engine shutdown.

Abstract: A secondary air injection system for improving emissions of internal combustion engines. The secondary air injection system includes an engine cylinder head and exhaust system designed to be used with or without a secondary air system.

Abstract: A method for diagnosing a secondary-air system of an internal combustion engine. The secondary-air system introduces secondary air into the exhaust-gas region of the internal combustion engine, the secondary air exothermically reacting together with combustible exhaust-gas components, and a thermoreactor being formed in the reaction region. The method provides for a measure of the secondary air to be ascertained from the thermal behavior in the thermoreactor and evaluated. The measure of the secondary air, which reflects, for example, the volumetric flow rate of the secondary air, the mass flow rate of the secondary air, or the amount or mass of secondary air flowing in a time interval, is compared to at least one threshold value. At least one diagnostic signal is then generated as a function of the comparison result.

Abstract: An engine system includes an engine, an intake fluid system, and an exhaust fluid system. Furthermore, the engine system includes a turbocharger device including a compressor member in operative communication with the intake fluid stream and an energy supply member in operative communication with the exhaust stream to be actuated thereby. The energy supply member transfers energy to the compressor member, and the compressor member supplies a compressed fluid stream to the engine. Moreover, the engine system includes an aftertreatment device in operative communication with the exhaust stream to treat the exhaust stream. The engine system additionally includes a bypass fluid system that bypasses the internal combustion engine. The bypass fluid system supplies the portion of the compressed fluid stream to the aftertreatment device.

Abstract: A system is disclosed including a primary engine that provides vehicle propulsion and a secondary engine that drives a generator to provide auxiliary power. The system further includes a first exhaust gas passageway from the primary engine and a second exhaust gas passageway from the secondary engine. The system further includes an emission treatment device including an exhaust inlet to treat exhaust from the primary and secondary engines. The system further includes an exhaust routing device that selectively routes exhaust from the first passageway or the second passageway to the exhaust inlet. The exhaust routing device at least partially blocks the first passageway or the second passageway from fluid communication with the exhaust inlet.

Abstract: A liquid reducing agent of a necessary amount according to an engine operating condition is injection-supplied from a nozzle having an injection hole opening to inside an exhaust gas passage, positioned on an exhaust gas upstream side of a nitrogen oxide reduction catalyst. On the other hand, when an injection flow rate of the liquid reducing agent becomes zero, compressed air stored in a purge air tank is supplied into the nozzle for a predetermined time. Thus, the liquid reducing agent remaining in the nozzle is forcibly discharged by the compressed air, and hence even if the nozzle is at a high temperature due to the exhaust heat, a situation where reducing agent constituents are deposited does not occur, and clogging of the inside of the nozzle can be prevented.

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: An aging device of a catalytic converter of a vehicle simulates wear-and-tear of a catalytic converter under conditions that simulate to those of a real vehicle by injecting an oil additive or an engine oil mixture containing phosphor (P), zinc (Zn), and etc., into an engine.

Abstract: There is provided an air supply apparatus for an engine comprising a plurality of exhaust pipes and catalysts arranged in the exhaust pipes, respectively, the apparatus comprising devices for supplying air into the interior of the corresponding exhaust pipes upstream of the corresponding catalysts, respectively.

Abstract: Heating device for the heating and gasification of urea or an urea solution, particularly for internal combustion engines, wherein said heating device is designed for installation in a gas line extending in a direction of flow and wherein said heating device has at least two gas-permeable heating surfaces that are spaced apart from each other in the direction of flow and that define a heating chamber. In order to create an improved heating device for stable urea gasification in an exhaust gas line that guarantees a uniform temperature distribution in the heating room as well as a quick response time, according to the invention an inlet opening is provided that discharges into the heating chamber between the at least two heating surfaces and through which the urea or urea solutions can be fed into the heating chamber.

Abstract: A method for controlling the amount of secondary air of a motor vehicle, which has a device for injecting secondary air. The increase in the injected amount of secondary air is carried out as a function of the starting conditions of the motor vehicle and the heating progression of the catalytic converter determined by modeling and/or measurement, and is variable over time.

Abstract: The present invention relates to a secondary air injection system for an internal combustion engine, and an automotive vehicle comprising such a secondary air injection system. The arrangement includes shut-off valve for selectively passing on or restricting airflow form the secondary air injection system. A flexible connector is arranged to receive the airflow and pass it on to at least two reed-type non-return valves arranged to substantially only allow airflow in the downstream direction. At the downstream side of each respective reed-type non-return valve a conduit for communicating any airflow passed there through to an associated exhaust bank of the internal combustion engine.

Abstract: In a secondary air supply device comprising a turbine and a compressor with turbine and compressor wheels having blades which are covered by wheel covers and an air filter structure disposed between the turbine and compressor wheels, so that air is supplied to the compressor and to the turbine from a common filter structure disposed between the compressor and the turbine wheels.

Abstract: Injection of secondary air into an exhaust of an automotive vehicle at a location upstream of a catalytic converter of the vehicle in which the airflow rate is calculated by the air injection system pressure and by the pulsation of the air injection system pressure in reference to stored values in a data table.

Abstract: The exhaust gas purification device has a first chamber having an exhaust pipe inlet, an ambient air inlet, and an exhaust gas outlet. A Venturi is arranged within the chamber, having an inlet end communicating with an ambient air inlet, a throat, and an outlet end communicating with an exhaust gas outlet. The Venturi has an exhaust gas inlet between its inlet end and its outlet end, receiving exhaust gas from within the chamber, directed generally towards the outlet end of the Venturi, so that ambient air and exhaust air are mixed in passing through the Venturi to its exhaust gas outlet. A perforated pipe within the first chamber receives the exhaust gas, and the exhaust gas escapes there from via the perforations, into the chamber and thence to the Venturi. A second chamber, having a catalytic substrate assembly mounted therein, receives the mixed ambient air and exhaust air from the exhaust gas outlet of the Venturi, and has an exhaust pipe outlet.

Abstract: A post-injection method for the regeneration of a device used to filter diesel engine exhaust gases. The method includes injecting a fully-pulverized hydrocarbon-, alcohol- and/or reducing-agent-type regeneration solution upstream of the oxidation catalyst (14) to increase the exhaust gases' temperature upon detection of clogging of the filter with particles. A computer uses temperature (2) and pressure (3) sensors disposed upstream of the filtration device to control injection of the regeneration solution from an electromagnetic injector (9). The regeneration solution is directed through a capillary (12) into the exhaust pipe (1) at a point located at a good distance from the injector, upstream of the catalyst (5), in order to be finely pulverized by the air.

Abstract: A regeneration assembly includes a first portion including a combustion chamber connected to a combustor head. The regeneration assembly also includes a second portion including a housing. The first portion is removably connectable to the second portion.

Abstract: A control device of an internal combustion engine suppressing catalyst deterioration by prohibiting fuel cuts, wherein the generation of odor from the catalyst after deceleration is suppressed. The control device is provided with a fuel cut executing device for stopping the supply of fuel to an internal combustion engine when a vehicle is in a decelerating state and a fuel cut prohibiting device for prohibiting a fuel cut when a temperature of a catalyst provided in an exhaust system is a predetermined temperature or more, wherein when a fuel cut is prohibited by the fuel cut prohibiting device when the vehicle decelerates in a predetermined period after an increased fuel operation is performed, the internal combustion engine is operated so that the combustion air-fuel ratio becomes lean in the decelerating state or in the decelerating state and its succeeding idling state.

Abstract: An apparatus comprises a combustion engine, an emission abatement device, and a turbocharger. The emission abatement device is fluidly coupled to the engine to receive exhaust gas therefrom. The turbocharger comprises an air compressor that is fluidly coupled to the engine to supply pressurized air to the engine and that is fluidly coupled to the emission abatement device via a flow path not including any combustion section of the engine to supply pressurized air to the emission abatement device. An associated method is disclosed.

Abstract: A secondary air supply system for an internal combustion engine includes: a cylinder head of the internal combustion engine having a plurality of exhaust holes and a plurality of supply holes formed thereon; a supply path communicating the exhaust holes and the supply holes so as to supply secondary air into the supply holes; an exhaust manifold attached to the cylinder head, and provided with a flange having a plurality of communication holes penetrating the flange; a lower shell including connection holes respectively corresponding to the communication holes, the lower shell being secured to the flange such that the communication holes and the connection holes are aligned; and an upper shell combined with the lower shell so as to form the supply path, communicated with the plurality of connection holes, between the lower shell and the upper shell.

Abstract: A secondary air supply system includes a supply passage, a valve, and a detecting unit. Secondary air is supplied to the upstream of a purification apparatus in an exhaust passage of an engine through the supply passage. The valve communicates and blocks the supply passage to be in open and close conditions. The detecting unit detects a detection object of secondary air in the upstream of the valve in the supply passage. A diagnosis apparatus for the secondary air supply system includes a diagnosis unit that obtains a detection result of the detecting unit in each of the open and close conditions of the valve for evaluating an abnormity of the secondary air supply system in accordance with the detection result. The diagnosis apparatus includes a reliability maintaining unit that determines the diagnosis operation of the diagnosis unit to be valid when the detecting operations in the open and close conditions are continuously performed.

Abstract: A four-cycle engine is provided that includes an exhaust port for releasing combusted gas from the engine and an exhaust system. The exhaust system includes an exhaust pipe coupled with the exhaust port, a first catalyst, a second catalyst, and a secondary air introduction pipe. The first catalyst is disposed in the exhaust pipe and the second catalyst is disposed in the exhaust pipe a set distance downstream of the first catalyst. The secondary air introduction pipe is configured to introduce air into the exhaust pipe. The secondary air induction pipe is connected to the exhaust pipe between the first and the second catalysts at a location where a temperature difference of the first and the second catalysts in a cold start transient phase is within a predetermined range.

Abstract: In an internal combustion engine having a compressor in its induction system which has a compressor wheel rotatably mounted in an intake duct combustion air compressor, whereby the combustion air is compressed to an increased boost pressure, and an auxiliary duct which opens into the compressor intake duct, an adjustable blocking element being arranged in the compressor intake duct upstream of the compressor wheel and an adjustable swirl device being arranged in an opening region of the auxiliary duct, and an NOx storage catalytic converter being disposed in the exhaust gas system, the blocking device and the swirl device are adjustable so as to generate an air fuel ratio with an excess of fuel, and, at the same time a propulsive swirl is applied to the compressor wheel when the blocking element is moved to a position in which air supply to the compressor intake duct is restricted.

Abstract: In a device for restraining the deterioration of a catalytic apparatus of an internal combustion engine of the present invention, when the temperature of the catalytic apparatus arranged in the engine exhaust system is higher than a predetermined temperature in a vehicle deceleration, a fuel-cut of the engine is prohibited and a first motor-generator MG2 connected with the vehicle drive shaft 6 is operated as a generator to charge an electrical accumulator 8.

Abstract: The present invention relates to an exhaust system for an internal combustion engine, having an exhaust line for removing exhaust gas from the internal combustion engine and having a secondary fuel supply for introducing secondary fuel into the exhaust gas of the internal combustion engine. To improve the introduction of the secondary fuel into the exhaust, a recirculation device is connected to the exhaust line and to the secondary fuel supply so that the introduction of secondary fuel into the exhaust is accomplished via or through the recirculation device. The recirculation device has a circulation space which receives an exhaust substream from the exhaust line in which the secondary fuel is introduced into the exhaust substream and from which the modified exhaust substream is returned to the exhaust line.

Abstract: A compact reversing flow catalytic converter with protection from overheating includes a valve unit which directs exhaust gases through a container filled with catalytic material to permit a bypass of catalytic material when a temperature of the material exceeds a predetermined threshold. The container defines a U-shaped gas passage that communicates with two ports at the top of the container. The valve unit is mounted to the top of the container and includes an intake and an exhaust cavity. The valve unit includes a valve disk having two openings therethrough. The valve disk rotates around perpendicular central axis between a first, a second and third positions. When overheating of the catalytic material is predicted, a controller relinquishes control of the valve disk and a center return mechanism rotates the valve disk to a third position, in which each of the openings communicates with both ports so that the exhaust gas flow bypasses catalytic material.

Abstract: Injection of secondary air into an exhaust of an automotive vehicle at a location upstream of a catalytic converter of the vehicle in which the airflow rate is calculated by the air injection system pressure and by the pulsation of the air injection system pressure in reference to stored values in a data table.

Abstract: A valve device includes a control valve for manipulating a communication between a first fluid channel and a second fluid channel. The valve device further includes a pressure sensor for detecting pressure in the first fluid channel. The pressure sensor is provided on a side face defining the first fluid channel. The pressure sensor has a pressure detection face directly opposed to the first fluid channel. The pressure detection face is substantially in parallel with a first axis of the first fluid channel.

Abstract: A fuel injection amount control device is used for an internal combustion engine. A secondary air supply device supplies secondary air into an exhaust passage of the internal combustion engine. Flow amount calculating circuitry calculates a secondary air flow amount. The secondary air flows into the exhaust passage. Target air fuel ratio setting circuitry sets a target air fuel ratio when secondary air is supplied. Fuel amount correcting circuitry corrects a fuel injection amount in accordance with a current value of the secondary air flow amount such that the air fuel ratio on a downstream side of an inlet of secondary air in the exhaust passage becomes the target air fuel ratio when secondary air is supplied. Target changing circuitry monitors increase and decrease in the secondary air flow amount. The target changing circuitry changes the target air fuel ratio to one of a rich side and a lean side in accordance with the increase and decrease in the secondary air flow amount.

Abstract: A forced regeneration device which performs regeneration of a particulate filter includes oxidation catalysts (23, 24a) disposed upstream from the particulate filter or in said particulate filter and a burner (30) located upstream from the oxidation catalysts and operable switching between a combustion mode for combusting a fuel spray by inflammation to raise temperature of exhaust gases in an exhaust passage and a fuel supply mode for supplying only a fuel spray to the exhaust passage without inflammation. After the burner operates in the combustion mode, the burner operation is switched to the fuel supply mode.

Abstract: An exhaust gas recirculation system for a power source, has at least one inlet port configured to receive at least a portion of a flow of exhaust produced by the power source. The exhaust gas recirculation system also has an electrode disposed upstream of the at least one inlet port and configured to charge particulate matter in the flow of exhaust. The exhaust gas recirculation system further has at least one collection surface configured to allow the at least one electrode to repel the charged particulate matter away from the at least one inlet port towards the at least one collection surface.

Abstract: An aftertreatment burner for an exhaust treatment device is disclosed. The aftertreatment burner may have a mounting member, and a canister connected to the mounting member to form a combustion chamber. The aftertreatment burner may also have a fuel injector disposed within the mounting member to selectively inject fuel into combustion chamber, and an air supply line configured to supply air to the combustion chamber. The aftertreatment burner may further have an igniter disposed within the mounting member to ignite the fuel/air mixture, and a thermal couple configured to detect the ignition.

Abstract: A power source is provided for use with an exhaust gas recirculation and selective catalytic reduction system. The power source has a main air-intake passage fluidly connected to a first air-intake passage and a second air-intake passage. A first cylinder group may be fluidly connected to the first air-intake passage and a first exhaust passage, wherein the first exhaust passage may include an ammonia-producing catalyst configured to convert at least a portion of a fluid in the first exhaust passage into ammonia. Further, a second cylinder group may be fluidly connected to the second air-intake passage and a second exhaust passage. A third cylinder group may be fluidly connected to the second air-intake passage. The power source may have a recirculation loop that includes the second air-intake passage and the third cylinder group.

Abstract: A secondary air pipe is connected to an exhaust pipe upstream of a catalyst, and a secondary air pump is connected to an upstream portion of the secondary air pipe. An ECU determines an operating period of the secondary air pump before the secondary air pump is operated in order to drive the secondary air pump within the operating period. Especially, the ECU detects a pump driving load during a secondary air supply to correct the operating period of the secondary air pump based on the detected pump driving load.