Abstract: A gas turbine engine component includes a wall having first and second wall surfaces, a cooling hole extending through the wall and a convexity. The cooling hole includes an inlet located at the first wall surface, an outlet located at the second wall surface, a metering section extending downstream from the inlet and a diffusing section extending from the metering section to the outlet. The diffusing section includes a first lobe diverging longitudinally and laterally from the metering section and a second lobe adjacent the first lobe and diverging longitudinally and laterally from the metering section. The convexity is located near the outlet.

Abstract: The present application provides a turbine blade cooling system. The turbine blade cooling system may include a first turbine blade with a first turbine blade platform having a cooling cavity in communication with a pressure side passage and a second turbine blade with a second turbine blade platform having a platform cooling cavity with a suction side passage. The pressure side passage of the first turbine blade platform is in communication with the suction side passage of the second turbine blade platform.

Abstract: Modified turbine components include an original turbine component comprising an outer wail enclosing an internal cavity, wherein the outer wall has an original portion removed therefrom to expose the internal cavity, and, an internally cooled supplemental element joined to the outer wall that replaces the original portion removed from the outer wall and re-encloses the internal cavity. The internally cooled supplemental element comprises one or more cooling channels that circulate air from the internal cavity through at least a portion of the internally cooled supplemental element.

Abstract: A fan blade having a body with a dovetail and an airfoil extending radially outwardly. The airfoil includes a pair of skins spaced to form an internal core, which define a pressure side and a suction side, and extending from a radially inner end to a radially outer tip. The core receives a plurality of braided tubes, with the tubes extending with at least a component in a radially outward direction. A fan and an engine are also described.

Abstract: A turbine airfoil including an airfoil body is disclosed. The airfoil includes a leading edge, a trailing edge, an exterior surface including a suction side extending from the leading edge to the trailing edge and a pressure side extending from the leading edge to a trailing end. The pressure side is located opposite to the suction side on the airfoil body. The complete pressure side of the exterior surface is coated by a thermal barrier coating with a thickness decreasing towards the trailing end.

Abstract: A locking spacer assembly for securing adjacent rotor blades includes a first end piece having a platform portion and a root portion that define a first inner surface of the first end piece. The root portion defines a first projection and an opposing second projection of the first end piece. The first projection has an outer profile adapted to project into a first lateral recess of the attachment slot. The second projection has an outer profile adapted to project into a second lateral recess of the attachment slot. A second end piece fits between the first inner surface of the first end piece and a sidewall portion of the attachment slot and includes a platform portion and a root portion. A borehole extends continuously through the first end piece and the second end piece. A fastener configured to engage with a sidewall portion of the attachment slot extends through the borehole.

Abstract: A bimetallic ring for use as a turbine shroud in a gas turbine engine. The bimetallic ring forms a sealing surface as a hot gas flow path boundary in the engine. The ring is comprised of two materials. The first material, a wrought, oxidation resistant metal alloy comprises a first portion, which is the hot gas flow path sealing surface. The second material, a low cost low alloy steel, comprises a second portion that may be at least a pair of supporting side plates. A dissimilar weld joint joins the sealing surface to the second portion, the at least pair of supporting side plates.

Abstract: A housing structure for a turbo-engine, especially for a gas turbine or an aircraft engine, includes an outer housing wall and an inner housing wall, the inner and outer housing walls annularly enclosing a flow channel for the turbo-engine and being spaced apart radially from the flow channel. At least one heat shield is arranged between the inner and outer housing walls, and a bar or a fixture projects at least somewhat radially from the inner housing wall. The bar or the fixture has on at least one side a broadening element that includes a sealing face against which the heat shield is positioned in a sealing manner.

Abstract: A turbine section has a turbine rotor carrying turbine blades. The turbine blades include seal members at a radially inner location. A vane section is formed of a plurality of circumferentially spaced vane components, each of which has an airfoil extending radially outwardly of a platform. A first seal member is fixed to the platform, and is positioned to be adjacent a seal from a blade which is positioned in one axial direction relative to the first seal member. A second seal member extends circumferentially beyond at least a plurality of the vane components and is positioned to be adjacent a seal member of a blade on an opposed axial side from the first blade. A vane component is also disclosed and claimed.

Abstract: A floating air riding seal for a gas turbine engine with a rotor and a stator, an annular piston chamber with an axial moveable annular piston assembly within the annular piston chamber formed in the stator, an annular cavity formed on the annular piston assembly that faces a seal surface on the rotor, where the axial moveable annular piston includes an inlet scoop on a side opposite to the annular cavity that scoops up the swirling cooling air and directs the cooling air to the annular cavity to form an air cushion with the seal surface of the rotor.

Abstract: Sealing device for providing seals between adjacent components, and turbomachines utilizing such sealing devices, are provided. A sealing device includes a seal plate insertable between the adjacent components, the seal plate comprising a first face and an opposing second face. The sealing device further includes a plurality of pins extending from one of the first face or the second face, the plurality of pins configured to space the one of the first face or the second face from contact surfaces of the adjacent components.

Abstract: The present invention relates to a gas turbine having a housing (1), an outer sealing ring (2) that can be fastened detachably to the housing, a clamping member (3) for clamping the outer sealing ring and the housing together radially, and a rotation locking member that has at least one housing groove (10) and a radial flange (20) of the outer sealing ring that can be locked against rotation in the housing groove in form-fitting manner with play (sa) in the axial and/or peripheral direction.

Abstract: A gas turbine engine includes a front center body case structure. A geared architecture is at least partially supported by the front center body case structure. A bearing structure is mounted to the front center body case structure to rotationally support a shaft driven by the geared architecture, the shaft drive a fan. A bearing compartment passage structure is in communication with the bearing structure through the front center body case structure. A method is also disclosed.

Abstract: In a steam valve, a seat-side convexly curved surface (35b) of a valve body (30) is configured such that the average radius of curvature Rv from a starting end portion (35c) on the upstream side in a flow direction of steam to a termination end portion (35a) has a relationship of Rv<Rs with respect to the radius of curvature Rs of a valve-seat-side convexly curved surface (26a); the seat-side convexly curved surface (35b) is formed with an upstream-side curved surface (36) and a downstream-side curved surface (37); the seat-side convexly curved surface (35b) has an abutting area (35s) abutting a valve seat portion (26); and the radius of curvature R1 of the downstream-side curved surface (37) has a relationship of Rs<R1 with respect to the radius of curvature Rs in the flow direction of the steam.

Abstract: A borescope assembly includes a first borescope plug comprising a first perimeter geometry portion. Also included is a second borescope plug comprising a second perimeter geometry portion distinct from the first perimeter geometry portion. Further included is a first borescope hole comprising a first hole geometry portion corresponding to the first perimeter geometry portion of the first borescope plug. Yet further included is a second borescope hole comprising a second hole geometry portion corresponding to the second perimeter geometry portion of the second borescope plug.

Abstract: An oil supply system for a propeller turbine engine including a propeller, a propeller gearbox connected to the propeller and a propeller adjusting device for altering the pitch angle of the propeller blades. The system includes an oil circuit and a propeller main pump for supplying the propeller gearbox and a propeller high-pressure pump supplying the propeller adjusting device with oil. The system includes an oil accumulator for providing, in the event of an undersupply of oil by the propeller main pump, oil contained in the oil accumulator to the inlet of the propeller high-pressure pump such that the pump inlet pressure at the inlet of the propeller high-pressure pump does not fall short of a certain minimum value. The oil accumulator is incorporated into the inflow to the propeller high-pressure pump to be continuously supplied and charged with oil of the propeller main pump.

Abstract: A turbo compressor includes a housing in which lubrication oil is accumulated, a gear that is housed in the housing and to which the lubrication oil is supplied, a demister that is disposed above the gear and on which an intake is provided to catch oil mist of the lubrication oil in the housing, a gear cover that is provided surrounding the gear to catch lubrication oil splashed by the gear and then drip the caught lubrication oil downward, and a demister cover that is disposed near the demister to drip the lubrication oil caught by the demister downward. Here, a narrow gap is formed between the demister cover and an inner wall surface of the housing. According to the turbo compressor, an amount of lubrication oil flowing through the demister can be reduced by the gear cover and the demister cover.

Abstract: An augmentor assembly for a gas turbine engine includes an alignment assembly disposed along an axis having a base and a plate. The base includes a plurality of grooves. The plate includes a plurality of flanges in mating engagement to the plurality of grooves. A first component and a second component are attached to the alignment assembly. The mating engagement of the plurality of grooves and the plurality of flanges is arranged to provide incremental adjustment to define a position of the first component relative to the second component.

Abstract: According to one embodiment, a carbon-dioxide-recovery-type steam power generation system comprises a boiler that produces steam and generates an exhaust gas, a first turbine that is rotationally driven by the steam, an absorption tower allows carbon dioxide contained in the exhaust gas to be absorbed into an absorption liquid, a regeneration tower that discharges the carbon dioxide gas from the absorption liquid supplied from the absorption tower, a condenser that removes moisture from the carbon dioxide gas, discharged from the regeneration tower, by condensing the carbon dioxide gas using cooling water, a compressor that compresses the carbon dioxide gas from which the moisture is removed by the condenser, and a second turbine that drives the compressor. The steam produced by the cooling water recovering the heat from the carbon dioxide gas in the condenser is supplied to the first turbine or the second turbine.

Abstract: A structure and method are provided for preventing or at least minimizing thermally-induced structural distortions, such as may occur when a steam turbine is cooling down. The steam turbine may include an inner housing and an outer housing. An intermediate space is formed between the inner housing and the outer housing, and sealing steam may be injected into the intermediate space to avoid the formation of temperature strata in the interspace and thus prevent the outer housing from bowing.

Abstract: A combined cycle plant (10) including: a gas turbine engine (12) having a compressor (14), a combustor and a gas turbine (16); a heat recovery steam generator (20) (HRSG) configured to receive exhaust from the gas turbine engine; a steam turbine (22, 24) configured to receive steam from the HRSG; a supplemental air arrangement (40) configured to generate supplemental heated air (42) when operating and to operate independent of the gas turbine engine; and a kettle boiler (26, 28) configured to use heat from the supplemental heated air to generate steam used in the steam turbine.

Abstract: A heat recovery steam generator has a plurality of heat exchangers, including superheaters 28, 30, an evaporator 32 and an economizer 34, disposed in a duct 27 along the flow direction of an exhaust gas 25 from a gas turbine 14, and generates steam by utilizing the exhaust gas 25 from the gas turbine 14. The heat recovery steam generator includes: auxiliary combustors 50, 52, each disposed upstream of one of the heat exchangers, for heating the exhaust gas by means of burners; and an air supply device for supplying air to the burners of the auxiliary combustor 52 from the outside of the duct.

Abstract: A camshaft module may include a shaft and at least one functional element. The functional element may have a functional element opening through which the shaft passes. The functional element may be fixed to the shaft in a seat portion of the shaft. The camshaft module may include a bearing arrangement in which at least one bearing portion of the shaft is mounted. The shaft may include at least one adjusting portion axially adjacent to the at least one seat portion. The adjusting portion may have a first outer diameter smaller than a second outer diameter of the seat portion. The functional element opening may have an inner diameter smaller than the second outer diameter of the seat portion and larger than the first outer diameter of the adjusting portion such that a press fit fixing is realized between the functional element and the seat portion of the shaft.

Abstract: A switchable roller finger follower including a combined lost motion spring and hydraulic lash adjuster clip is provided. The switchable roller finger follower includes at least one spring having two coiled spring portions. Each of the two coiled spring portions is wrapped around a respective spring holding pin formed on an inner elongated body. Each one of the at least two coiled spring portions includes a first leg and a second leg. The first legs each extend from a respective one of the two coiled spring portions to engage a spring pallet formed on an outer elongated body. The second legs each contact a bottom portion of the inner elongated body in proximity to a socket portion to act as a retainer for retaining a hydraulic lash adjuster to the inner elongated body.

Abstract: [Problems to be Solved] In the valve opening and closing timing controlled by an ECU, since the responsivity of a phase varying apparatus becomes low and the valve opening and closing timing cannot be appropriately controlled in the state of low engine rpm, desired engine characteristics cannot be obtained. Therefore, it is a problem to be solved by the present invention to provide a method and an apparatus for controlling a phase varying apparatus capable of obtaining the considerably high responsiveness of the phase varying apparatus under condition of low engine rpm.

Abstract: A valve stem seal including a radially outwardly extending flange that includes one or more circumferential grooves to allow the flange to flex and lay flat against a support surface and protect the flange from fatigue.

Abstract: An internal-combustion engine includes a system for variable actuation of intake valves, including a control valve for each cylinder, which controls communication of a pressurized-fluid chamber with a discharge channel. The control valve has at least three different positions, namely, a first completely open position, a second partially open position, and a third completely closed position. Electronic control means are programmed for keeping the control valve in its closed position in operating stages in which the intake valve must remain coupled to the respective cam and for bringing the control valve from its completely closed position to its partially open position or to its completely open position in operating stages in which the intake valve must be uncoupled from the respective cam, selection between the first position and said second position of the control valve being made as a function of one or more operating parameters of the engine.

Abstract: An auxiliary valve actuating mechanism of an engine includes a first valve actuating mechanism and an auxiliary valve actuating mechanism. The auxiliary valve actuating mechanism comprises an auxiliary cam, an auxiliary rocker-arm shaft, an auxiliary rocker arm, an eccentric rocker arm bushing and a bushing actuation device. One end of the auxiliary rocker arm constitutes a motion pair with the auxiliary cam and the other end is above the valve. The bushing actuation device actuates the eccentric rocker arm bushing to rotate between an operating position and a non-operating position.

Abstract: Methods and systems are provided for an oil pump mounting structure that provides accessibility and removal of the oil pump without removing a balancer shaft. While periodically servicing or replacing the oil pump may be necessary throughout the lifetime of an engine, it is desirable to allow for easy removal of the oil pump without removing and reassembling other engine components. To provide alignment and a rigid connection between the oil pump and engine frame while allowing for removal of the oil pump without removing other components, dowel bolts with unthreaded, threaded, and dowel portions are used to mount the oil pump to the engine frame.

Abstract: Methods and systems are provided for using a crankcase vent tube pressure or flow sensor for diagnosing a location and nature of crankcase system integrity breach. The same sensor can also be used for diagnosing air filter plugging and PCV valve degradation. Use of an existing sensor to diagnose multiple engine components provides cost reduction and sensor compaction benefits.

Abstract: A non-return valve for an oil return in the crankcase ventilation system of a combustion engine includes a valve housing, a valve body which is mounted in the valve housing so as to be displaceable as a whole between an open position and a closed position, wherein the valve body in the non-operating state of the combustion engine is maintained in the open position without preload and the valve body is configured to automatically move to the closed position in case of an overpressure at the crankcase side with respect to the oil separator chamber. The non-return valve is provided and configured to be inserted into a mounting of a cylinder head cover of the combustion engine.

Abstract: A system and method for managing the characteristics of engine oil in a lubrication system for an internal combustion engine is disclosed. Generally speaking, the method includes the steps of determining a target viscosity for the engine oil based on engine speed and engine load, determining a working viscosity which may be directly measured or determined based on engine oil temperature and engine oil type, comparing the target viscosity to the working viscosity, deriving a target engine oil temperature, and directing engine oil to one of an oil cooler, an oil heater, or neither when and until the target engine oil temperature is achieved.

Abstract: A system including a lubrication delivery tube and a bearing for an engine provides high reliability through an externally-supplied lubrication. The system may be supplied as a kit including a lubrication delivery tube and an oil filter adapter having a port for supplying the external lubrication to a mounting flange of the bearing.

Abstract: Fastening method, assembly and structure of engine oil fill extension tube can include an oil fill extension tube and a self-locking washer. The oil fill extension tube can include a plurality of locking edges disposed towards a first distal end of the oil fill extension tube, where the plurality of locking edges can define boundaries of a plurality of slots. The self-locking washer can include a plurality of teeth disposed on its top surface. The self-locking washer can be oriented over an opening in the oil pan, after which the oil fill extension tube can be threaded into the opening. The plurality of slots and plurality of teeth can be ratcheted together to fasten the oil fill extension tube into the oil pan when the oil fill extension tube is rotated clockwise. The washer can further include a locking extension to securely engage a portion of the oil pan.

Abstract: A heating device of a PCV valve includes a PCV valve, a conduit and a bush. The PCV valve contacts the bush. The bush includes an outward protrusion. The outward protrusion includes a curved surface contacting an outside surface of the conduit in a manner of a surface-to-surface contact. Therefore, when the conduit is heated by engine cooling water, the bush contacting the conduit in the manner of a surface-to-surface contact is heated and the PCV valve contacting the bush is heated. Therefore, the PCV valve can be heated by the engine cooling water.

Abstract: A sound generator, for a system for influencing sound waves propagating through an exhaust system of a vehicle driven by an internal combustion engine, includes an enclosure comprised of an upper shell and a lower shell. A bell mouth, supported by the lower shell and penetrating the lower shell, is configured for a fluid communication with the exhaust system. A loudspeaker is disposed in the enclosure and supported by the bell mouth. The lower shell of the enclosure supports the upper shell of the enclosure. The bell mouth is solely supported by the lower shell of the enclosure. The lower shell may include at least one air-tight feed-through for a control wire connected to the loudspeaker and/or at least one pressure equalizing valve. An anti-sound system is provided that includes the sound generator and a vehicle is provided with the anti-sound system.

Abstract: An exhaust gas purifying device is disposed in a portion of a motor section rearwardly of a vehicle body. A cylindrical mixing exhaust pipe is provided in a distal end portion of an exhaust pipe, through which exhaust gas discharged from the exhaust gas purifying device flows. The mixing exhaust pipe has a larger diameter than the exhaust pipe to overlap the exhaust pipe in a radial direction for drawing ambient air by the exhaust gas discharged from the exhaust pipe and mixing drawn air with the exhaust gas to discharge the mixed gas to the outside from a discharge opening. The mixing exhaust pipe is arranged in a lower side position of the motor section on one side of the vehicle width direction with the exhaust gas being discharged toward the front of the vehicle body.

Abstract: This disclosure relates generally to the use of gas clathrates. More particularly, this disclosure relates to systems, methods, and apparatuses related to the use of gas clathrates as a fuel source for automobiles. The gas clathrates may first be dissociated into at least one gas and the at least one gas delivered to the prime mover of a vehicle or the gas clathrates may be directly utilized by the prime mover as a fuel source.

Abstract: A mixer configuration for mixing an additive with an exhaust gas stream includes at least one overflow surface which is disposed in a mixing section of an exhaust pipe. The exhaust pipe has a cross section and a main flow direction of the exhaust gas stream. The at least one overflow surface is disposed centrally in the mixing section, is directed along the main flow direction of the exhaust gas stream and has a multiplicity of closed depressions. The mixer configuration permits an excellent mixture of the exhaust gas stream with an additive, without generating a high flow resistance in the process. A motor vehicle having a mixer configuration is also provided.

Abstract: It is an object of the present invention to provide an exhaust gas treatment device of an engine capable of preventing matching surfaces of catalyst portions configuring a combustible gas catalyst from being thermally damaged. In the exhaust gas treatment device, combustible gas is produced by combustible gas generating catalyst, exhaust gas heated by combustion of combustible gas is supplied to an exhaust gas treatment portion, the combustible gas generating catalyst comprises an aggregate of a plurality of catalyst portions, each of the catalyst portions includes a matching surface with respect to adjacent one of the catalyst portions, a fastening ring is fitted over the combustible gas generating catalyst in which the matching surfaces of the adjacent catalyst portions are abutted against each other, and the matching surfaces of the adjacent catalyst portions are brought into tight contact with each other by a fastening force of the fastening ring.

Abstract: This burner has: a flame stabilizer formed in a tubular shape; a fuel supply unit that supplies fuel within the flame stabilizer; an air supply passage that includes a heater unit for heating air and that supplies air heated by the heater unit into the flame stabilizer; and an ignition unit that ignites the air-fuel mixture of combustion air and fuel within the flame stabilizer.

Abstract: The invention relates to an exhaust gas treatment system comprising a catalytic particulate filter, a catalytic reduction device for the reduction of nitrogen oxides, which is mounted downstream of the catalytic particulate filter, an injection device mounted upstream of the catalytic particulate filter, a means for determining the temperature of the catalytic particulate filter and an electronic control unit able to command injection of reducing agent. The electronic control unit comprises a first control means able to command injection of the reducing agent in order to obtain a reference quantity of reducing agent stored in the filter that corresponds to a filter temperature below a threshold, and a second control means able to command the injection of reducing agent in order to obtain a reference quantity of reducing agent stored in the device that corresponds to a filter temperature higher than said threshold.

Abstract: It is an object of the present invention to provide a diesel engine in which a DPF case and an SCR catalyst case can be placed compactly. The diesel engine includes an engine body, the DPF case and the SCR catalyst case, a DPF is accommodated in the DPF case, an SCR catalyst is accommodated in the SCR catalyst case, and the DPF case and the SCR catalyst case are mounted on the engine body. The SCR catalyst case is placed in a direction which extends along the DPF case. The DPF case is placed directly above a flywheel housing and right behind a cylinder head cover, and the SCR catalyst case is placed directly above the cylinder head cover.

Abstract: The invention relates to a method to determine the HC-conversion efficiency of a catalyst, which is situated in the exhaust gas flow path of an internal combustion engine and which is configured to convert hydrocarbons, by means of an oxygen-sensitive sensor that is installed downstream from the catalyst in the exhaust gas flow path and that exhibits a cross sensitivity to hydrocarbons. The method comprises: detecting a first signal of the downstream sensor in a first situation in which a first HC fraction is present in the exhaust gas upstream from the catalyst; detecting a second signal of the downstream sensor in a second situation in which a second HC fraction that is higher than the first HC fraction is present in the exhaust gas upstream from the catalyst; and determining the HC-conversion efficiency of the catalyst as a function of the first and second signals of the downstream sensor.

Abstract: A dosing valve for administering a reducing agent into an exhaust stream within an exhaust manifold of an internal combustion engine. The dosing valve includes a valve needle internally coaxial to a valve body and held in a closed position by a force of compressed spring acting axially and held in relation to the valve needle and valve body. The negative impact of varnish and dehydrogenated compounds, or coking products, of hydrocarbon based reducing agents, is substantially reduced or eliminated. Additionally, this includes decreased sensitivity to the negative impact of the precipitates and crystals that come out of the solution due to temperature change with urea-based reducing agents.

Abstract: A metering arrangement (3, 30) is proposed for a liquid exhaust-gas aftertreatment medium for the aftertreatment of the exhaust gas of an internal combustion engine which has an exhaust-gas system, in particular for a urea/water solution, having a delivery pump (7) and a metering module (13), wherein the delivery pump (7) is connected to a suction line (23) for sucking the exhaust-gas aftertreatment medium out of a tank (1), wherein the delivery pump (7) and the metering module (13) are connected to one another via a pressure line (25), and the exhaust-gas aftertreatment medium can be fed via the metering module (13) to the exhaust-gas system, wherein a recirculation pump (8) is arranged parallel to the delivery pump (7), wherein the recirculation pump (8) is connected on the suction side to the metering module (13). Furthermore, a corresponding method for metering is proposed.

Abstract: An exhaust gas heat energy recovery and pollution control system for a marine vessel is disclosed. The system includes (a) an exhaust gas boiler that receives exhaust gases from a gas or fuel oil-burning internal combustion engine, (b) a variable capacity wet scrubbing system that sprays a mixture into the exhaust gases, (c) two or more condensing heat exchangers that receive exhaust gases, (d) a variable flow and variable pressure exhaust gas mover that facilitates movement of the exhaust gases, (e) a liquid collection and treatment system that collects liquid condensate, (f) one or more heat sinks to receive thermal energy from exhaust gases, (g) an interconnecting fluid conduit that allows for movement of exhaust gases, and (h) a control system communicatively coupled with a plurality of sensors, actuators, and external interfaces.

Abstract: A heat exchanger, for an exhaust gas system (5) of an internal combustion engine (1), includes a thermoelectric module (13), converting thermal energy into electrical energy, having a hot side (17) and a cold side (18). A cooling pipe (15), for a cooling fluid, is arranged on the cold side (18) and a heating pipe (16) for a heating fluid, is arranged on the hot side (17). The cooling pipe (15) and the heating pipe (16) are stacked with the thermoelectric module (13) in a stacking direction (19) and form a stack (20). The heat transfer within the stack (20) is improved with at least one of the pipes (15, 16) being curved toward the thermoelectric module (13) at an outer pipe face (26) and with the thermoelectric module (13) curved toward the pipe (15, 16) at an outer module face (27) facing the particular pipe (15, 16).

Abstract: An exhaust gas purification system comprises an exhaust gas purification device which is arranged in an exhaust gas route of an engine, renewing devices, for burning and removing a particulate matter within the exhaust gas purification device, renewal advance notifying means which is actuated in the case that a clogged state of the exhaust gas purification device becomes equal to or more than a prescribed level, and renewal informing means which informs of a fact that the renewing devices are under operation. The renewal advance notifying means is actuated before actuating the renewing devices.

Abstract: Systems and methods for monitoring an exhaust gas sensor coupled in an engine exhaust are provided. In one example approach, a method comprises indicating exhaust gas sensor degradation based on a downstream exhaust gas sensor responding before the upstream exhaust gas sensor during a commanded change in air-fuel ratio.