Abstract: A compact intake device for a multicylinder engine includes fuel injection valves, vacuum conduits, and purge conduits compactly disposed on throttle bodies. First and second connecting tubes are disposed on a plurality of throttle bodies of a multicylinder engine and are open into intake passages in the throttle bodies substantially perpendicularly to the axes of the intake passages. The first and second connecting tubes are disposed in sandwiching relation to fuel injection valves. Purge conduits are connected to the first connecting tubes, and vacuum conduits are connected to the second connecting tubes.

Abstract: A marine fuel delivery system and method of construction thereof provides at least one of a fuel filter housing and a fuel vapor separator housing with a lower support cap extending laterally therefrom, with the lower support cap being formed as a single piece of plastic material with the fuel filter housing and/or fuel vapor separator housing. In addition, the system includes a heat shield extending upwardly from the lower support cap. The fuel filter housing and/or fuel vapor separator housing; the lower support cap and the heat shield are constructed as a monolithic piece of thermoset plastic that does not melt when directly exposed to a 650° C. flame for 2½ minutes.

Abstract: A fill head assembly for a fuel storage system includes a check valve disposed within a central region of the fill head assembly. The check valve includes a membrane covering a vent outlet of the fill head assembly. The check valve prevents liquid flow from the central region into the vent outlet, while simultaneously allowing vapor flow from the central region into the vent outlet. The membrane includes a micro-porous material that is liquid impermeable, thereby preventing liquid flow through the membrane, and is vapor permeable, thereby allowing vapor flow through the membrane.

Abstract: A canister purge valve for an internal-combustion engine is provided with a housing including a supply channel that connects a fuel-vapor inlet port to a fuel-vapor outlet port. A valve scat is disposed across the supply channel. A valve shutter has a pressure-compensating channel and is movably mounted within the supply channel to move from an “open” position, in which the valve shutter is distant from the valve seat, to a “closed” position, in which the valve shutter is pressed against the valve seat. A rigid stem is mechanically coupled to the valve shutter to move the valve shutter from the “open” position to the “closed” position and seals the; pressure-compensating channel in the “closed” position.

Abstract: A method and system for fuel vapor control in a hybrid vehicle (HEV). The HEV fuel vapor recovery system includes a fuel tank isolation valve, which is normally closed to isolate storage of refueling from storage of diurnal vapors. The method for fuel vapor control includes selectively actuating the fuel tank isolation valve during interrelated routines for refueling, fuel vapor purging, and emission system leak detection diagnostics to improve regulation of pressure and vacuum the HEV fuel vapor recovery system.

Abstract: A control module for an engine of a vehicle includes a mode determination module that determines whether the vehicle is in a fuel-saving mode based on an acceleration of the vehicle. A diurnal control valve (DCV) control module selectively closes a DCV a predetermined time after at least one of determining that the vehicle is in the fuel-saving mode and determining that the engine is stopped.

Abstract: An apparatus for determining an air-fuel ratio imbalance among cylinders based on an output value of an air-fuel ratio sensor, an imbalance determination parameter which becomes larger or smaller as a difference among air-fuel ratios becomes larger, and performs determining an air-fuel ratio imbalance among cylinders based on a result of a comparison between the imbalance determination parameter and a imbalance determination threshold. The determining apparatus calculates a purge correction coefficient which compensates for a change in the air-fuel ratio due to an evaporated fuel gas which is generated in a fuel tank, while the evaporated fuel gas is being introduced into an intake passage, and corrects a fuel injection amount with the purge correction coefficient FPG.

Abstract: A liquefied petroleum gas (LPG) fuel assembly may include a fuel rail and a flow control mechanism. The fuel rail may have an inlet in communication with a pressurized LPG fuel source, an injection passageway in communication with the inlet and a fuel injector that provides fuel to a combustion chamber of an engine, and an outlet in communication with the fuel injection passageway. The flow control mechanism may be in communication with the outlet of the fuel rail and a LPG fuel tank and may be operable in first and second modes. The second mode may provide a greater flow restriction than the first mode to control a fuel flow from the outlet of the fuel rail to the fuel tank.

Abstract: Disclosed is a fuel system for a traveling vehicle having an engine mounted on a vehicle body and a ROPS extending upward from the vehicle body. The fuel system includes a fuel tank accommodating an amount of fuel, a canister, an evaporating hose including a first evaporating hose portion and a second evaporating hose portion for sending fuel vapor generated inside the fuel tank to the canister. The first evaporating hose portion is connected to the fuel tank and extending upward from the fuel tank along a vertical post of the ROPS. The second evaporating hose portion extends downward along a vertical post of the ROPS and is connected to the canister.

Abstract: An outboard marine engine has vapor vent control apparatus including a fuel inlet in fluid communication with a fuel reservoir of the engine. The fuel inlet is operably attachable to a fuel pin of a fuel connector. When attached, liquid fuel flows to the fuel reservoir and when detached, liquid fuel flow out of the fuel inlet is prevented. A vapor vent passage is configured in fluid communication with the liquid fuel reservoir and an air intake of the engine. A vent pin is disposed in the vapor vent passage. The vent pin moves between a first position upon attaching the fuel connector to the fuel inlet and a second position upon detaching the fuel connector from the fuel inlet. In the first position, the vapor vent passage is open to fuel vapor flow and, when in the second position, the vapor vent passage is closed to fuel vapor flow.

Abstract: The invention relates to a method and a device for testing the tightness of a fuel tank of an internal combustion engine, in particular of a vehicle, with a pressure switch which communicates with the interior of the fuel tank, and a diagnosis means for testing the serviceability of the pressure switch by evaluating the switching status of the pressure switch. So that diagnosis of the pressure switch is possible even with the internal combustion engine shut off or the vehicle turned off and for internal combustion engines with exhaust gas turbochargers, it is proposed, according to the invention, that the diagnosis means test the opening behavior of the pressure switch when the temperature rises.

Abstract: A combustible fuel supply system includes a fuel tank, a carburetor and a combustible fuel piping system. The combustible fuel piping system includes a fuel-feeding pipe, a fuel-drawing pipe, a vent pipe, and a switch valve. The fuel-feeding pipe interconnects the carburetor and a lower space of the fuel tank that stores combustible fuel. The fuel-drawing pipe interconnects the carburetor and an upper space of the fuel tank that accommodates air when the lower space stores the combustible fuel. The vent pipe is for fluid communication between the upper space and the exterior of the fuel tank. The switch valve is operable to obstruct fluid flow through at least one of the fuel-feeding pipe, the fuel-drawing pipe and the vent pipe, and is operable to switch between a fuel-feeding state and a fuel-drawing state for obstructing and permitting fluid flow through at least one of the pipes.

Abstract: A fuel delivery system for a fuel burning engine of a vehicle and a method of operating the fuel delivery system is provided. As one example, the method includes separating a first fuel and a second fuel from a fuel vapor on-board the vehicle, said fuel vapor including at least an alcohol component and a hydrocarbon component and said first fuel including a higher concentration of the alcohol component than the fuel vapor and the second fuel; condensing the separated first fuel from a vapor phase to a liquid phase; delivering the condensed liquid phase of the first fuel to the engine; and combusting at least the condensed liquid phase of the first fuel at the engine.

Abstract: A valve device is used by being attached to a fuel tank. The valve device includes a main body portion provided with ventilation openings which become an inner end of a connecting passage with the outside of the fuel tank, a valve body opening and closing the ventilation openings using a liquid surface of a fuel, and a skirt portion extending down from the main body portion so as to surround the valve body, and also constructed so as to admit fuel due to a pressure difference between inside and outside of the fuel tank when the liquid surface of the fuel reaches a cuff portion of the skirt portion.

Abstract: An evaporative venting system for use in an internal combustion engine and a method for venting fuel vapors are disclosed. The evaporative venting system includes a containment chamber at least in indirect communication with a fuel tank and a passageway defined within the containment chamber and having an inlet opening and an outlet opening. The inlet opening is at least indirectly in communication with the fuel tank and the outlet opening is at least indirectly in communication with an evaporative chamber such that the passageway provides a vent path between the fuel tank and the evaporative chamber such that the vent path allows for both the venting of fuel vapors from the fuel tank and the intake of air into the fuel tank during all angles of positioning of the fuel tank.

Abstract: A fuel supply apparatus according to the present invention includes vapor production determining means for determining whether or not the vapor of the fuel is producible, and control means (ECU) for operating a passage resistance adjusting means of a pressure adjusting mechanism to cause increase of the pressure of the fuel supplied to an injector insomuch as the production of the vapor is inhibited when the vapor production determining means has determined a vapor producible condition.

Abstract: A delivery unit for delivering fuel from a fuel reservoir to an internal combustion engine of a motor vehicle. The delivery unit includes a fuel pump arranged in a swirl pot, a fuel filter arranged downstream of the fuel pump, and a valve arranged in the swirl pot. The valve is arranged downstream of the fuel filter and in a zone of the swirl pot that is continuously filled with fuel.

Abstract: Systems, methods, and computer readable storage media are described in which exhaust gas is routed to a hydrocarbon retaining device during starting, and purged to the engine intake manifold. Various alternative approaches are described for controlling operation and diagnosing degradation. Further, various interrelated configurations are described.

Abstract: A method, fuel system, and components for facilitating the delivery of liquid fuel from a fuel tank in fluid communication with a float bowl carburetor of an internal combustion engine, wherein evaporative emissions of the fuel from the fuel tank and float bowl carburetor are mitigated. During operation of the engine, fluid communication is permitted between the fuel tank and the carburetor, and fuel vapors at a predetermined threshold superatmospheric pressure are permitted to vent outwardly from the fuel tank. During inoperation of the engine, fluid communication is prevented between the fuel tank and the carburetor, and fuel vapors at a predetermined threshold superatmospheric pressure are permitted to vent outwardly from the fuel tank.

Abstract: A vent-on-demand fuel sump and vehicle fuel system having such a fuel sump are provided. The fuel sump may include a pressurized vessel and at least two sensors configured to detect a level of fuel within the vessel. A valve coupled to the vessel may be configured to release air and/or fuel vapor to the atmosphere. The fuel sump may also include a programmable electronic controller configured to modulate the valve between a closed position and an open position based on signals received from the sensors corresponding to the fuel level. The valve may be configured to remain in the closed position until the fuel level drops below a predetermined level and the controller sends a signal to open the valve to release air and/or fuel vapor from the vessel into the atmosphere. The vehicle fuel system having such a fuel sump may include a fuel container and an engine having an intake.

Abstract: A fuel vapor separator assembly including a housing having an open interior and a float disposed therein. At least one magnet is disposed on the float, and a sensor assembly which is responsive to magnetic fields is disposed externally of the housing. The sensor assembly senses the position of the float to determine whether vapor is present in the fuel vapor separator. If the sensor assembly determines that vapor is present in the fuel vapor separator, then it generates a signal, which a controller receives and activates a vapor vent valve to discharge the vapor and/or activates a fuel lift pump to pump additional fuel into the fuel vapor separator. The sensor assembly could be, for example, a Hall effect sensor or a reed-type sensor.

Abstract: This invention relates to an aerating device for a fuel system, and in particular, to an aerating device for a fuel system supplying fuel to an engine from a fuel tank. The invention includes, for example, a solenoid valve accessing a flow path to the fuel tank, and a control unit opening a closing the solenoid valve, such that opening of the solenoid valve permits fuel and air to flow back through the flow path to the fuel tank and naturally separate.

Abstract: A fuel tank vent system includes a carbon canister and an engine fuel system coupled to the carbon canister. Fuel vapor discharged from a fuel tank included in the engine fuel system flows during certain conditions into the carbon canister to encounter charcoal stored in the carbon canister. Hydrocarbon material associated with the discharged fuel vapor is captured by the charcoal and a stream of cleaned vapor is discharged from the carbon canister to the atmosphere.

Abstract: Fuel is evacuated from a fuel rail by directing liquid fuel from the fuel rail to a fuel tank and then by directing gaseous fuel from the fuel rail to a fuel vapor canister.

Abstract: A sleeve hydrocarbon trap is provided. In some examples, the sleeve hydrocarbon trap includes a hydrocarbon adsorbing sleeve, the sleeve adapted to be positioned in a sensor bore and the sleeve including one or more hydrocarbon adsorbing layers, and a cage adapted to retain the hydrocarbon adsorbing sleeve in the sensor bore.

Abstract: A fuel shut-off valve includes a casing, an ascendable and descendible float, and an upper valve element, which is actuated by the float to open and close connector passage that communicates the inside of fuel tank with the outside, and which includes a valve body and a ring-shaped seat member. The ring-shaped seat member makes a connector bore, which communicates with the connector passage, therein, and includes a base, a holding portion, a seating portion, a lip-shaped portion, and a thin-film-shaped portion. The seating portion opens and closes the connector passage, and defines an opening of the connector bore. The lip-shaped portion seats on and separates away from the float, and defines the other opening of the connector bore. The thin-film-shaped portion is disposed between the base and the lip-shaped portion, and is deformable elastically upon being pressed by the float when the float seats on the lip-shaped portion.

Abstract: A unitized fuel vapor separator and evaporative emission device; marine fuel system, and marine engine therewith are provided. The device includes a fuel vapor separator and evaporative emissions chamber having a common wall separating the fuel vapor separator from the evaporative emissions chamber. The fuel vapor separator is configured for fluid communication with an upstream fuel tank and with a fuel pump and has a fuel vapor outlet to channel fuel vapor outwardly therefrom. The evaporative emissions chamber is configured for fluid communication with the fuel tank to receive fuel vapor therefrom and has an adsorption material for adsorbing fuel vapor and dissipating air from the fuel vapor through an air outlet to channel the air outwardly therefrom.

Abstract: The switched state of a pressure switch in a tank ventilation system of a motor vehicle is used for testing the function of the tank ventilation system, the pressure switch being in a low-pressure position if the pressure in the tank ventilation system is lower than a predefined pressure limit while being in a high-pressure position if that is not the case. A defective pressure switch can result in wrong assessments. Disclosed is a method for testing the function of the pressure switch, the method encompassing the following steps: a switched state of the pressure switch is detected; a measure is carried out that increases the pressure in the tank ventilation system above the pressure limit if the pressure switch is in the low-pressure position; a defect of the pressure switch is identified if the pressure switch remains in the low-pressure position after carrying out the measure.

Abstract: An engine fuel supply system is provided at a reduced cost by using a HC dosing pump that supplies fuel into an exhaust pipe also as a pump for a cylinder fuel supply device. When a signal is generated to command air removal from a cylinder fuel supply passage, the dual-purpose pump is activated, a first on-off valve assumes an open state, and a second on-off valve assumes a close state, so that the fuel is supplied from the dual-purpose pump to the cylinder fuel supply passage via an air-removal fuel supply passage. When a signal is generated to command fuel supply into the exhaust pipe, the dual-purpose pump is activated, the second on-off valve assumes the open state, and the first on-off valve assumes the close state, so that the fuel is supplied from the dual-purpose pump to the exhaust pipe via the exhaust-pipe fuel supply passage.

Abstract: A fuel system for a vehicle with an engine includes: a fuel tank for storing fuel: first and second ports disposed on a wall of the fuel tank, between which wall and a fuel fluid level a clearance is created when the fuel is contained in an allowable maximal amount in the fuel tank of the vehicle in a horizontal state, the first and second ports being positioned frontward and rearward, respectively, in a longitudinal direction of the vehicle, and the first port and the second port being out of alignment in a lateral direction; a canister for adsorbing and releasing a fuel vapor; an inflow line for sending the fuel vapor generated in the fuel tank to the canister through the first and second ports; and a discharge line for sending the fuel vapor from the canister to an air-intake path to the engine.

Abstract: A marine vessel propulsion device includes an engine, a fuel injection device, an intake system, a vapor separator tank arranged to separate fuel vapor from liquid fuel to be supplied to the engine, a pump unit arranged to transport the fuel from the vapor separator tank to the fuel injection device, a fuel pipe arranged to connect the fuel injection device and the pump unit, a vapor pathway arranged to connect the vapor separator tank and the intake system, a valve disposed in the vapor pathway, and an engine control unit. The engine control unit is arranged to control the opening degree of the valve in accordance with a valve opening speed set based on at least the pressure of the fuel in the fuel pipe when starting the engine.

Abstract: Systems and methods for performing leak testing on fuel system components in hybrid vehicles during engine-off operating conditions are disclosed. For example, a fuel tank may include a pressure accumulator which may be filled with fuel via a fuel pump in order to generate a vacuum which may be used to diagnose leaks in the fuel system.

Abstract: A fuel line air trap for an unmanned aerial vehicle has a vessel in-line with a fuel line, fuel line connectors, and fuel inlet and outlet stems. The vessel contains an inlet at a distal end and an outlet at a proximal end. The fuel line connectors are attached to the vessel at the inlet and at the outlet to connect the fuel line to the vessel. The fuel inlet stem attaches to the vessel at the inlet and a fuel outlet stem attaches to the vessel at the outlet. Both the fuel inlet stem and fuel outlet stem protrude into the vessel a predetermined distance such that a gap exists between them. As air bubbles enter the gap in the fuel line air trap, they separate from the flow of fuel and migrate to the exterior walls of the vessel. The air bubbles are purged during remain trapped refueling.

Abstract: Systems and methods for an engine are described. In one example, a system may include a variable venturi coupled in an intake of the engine; an exhaust gas recirculation system having an exhaust gas recirculation flow path, the exhaust gas recirculation flow path coupled to the variable venturi; and a vacuum-utilizing device or system coupled to the variable venturi. In another example, a method may include coordinating adjustment of an exhaust gas recirculation valve coupled to the exhaust gas recirculation system, a fuel vapor purging valve coupled to the fuel vapor purging system, and the variable venturi in response to operating conditions.

Abstract: A fuel supply system for a vehicle may include a fuel tank including a mounting portion protruding downwards from an upper inner surface of the fuel tank, a fuel limit vent valve and a rollover valve that is connected with the fuel limit vent valve within the fuel tank, and a mounting plate connecting the fuel limit vent valve and the rollover valve and configured to be mounted onto the mounting portion of the fuel tank.

Abstract: A fuel rail vent system for evacuating air from a fuel rail includes a first fuel reservoir and a first fuel line extending between the first fuel reservoir and the fuel rail. A fuel pump is configured in fluid communication with the first fuel reservoir to pump liquid fuel from the first fuel reservoir to the fuel rail through the first fuel line. A second fuel line separate from the first fuel line extends between the first fuel reservoir and the fuel rail. A primer system is configured for fluid communication with the first fuel reservoir to pump liquid fuel from the first fuel reservoir to the fuel rail through the second fuel line. A second fuel reservoir separate from the first fuel reservoir is configured for fluid communication with the fuel rail downstream of the fuel rail to receive any excess liquid fuel and/or fuel vapor upstream therefrom.

Abstract: An evaporated fuel gas concentration learning section A8 renews an evaporated fuel gas concentration learning value based on a feedback correction amount FAF. An estimated purge rate calculating section A9 estimates, a flow of an evaporated fuel gas introduced into a combustion chamber based on a flow KP of an evaporated fuel gas passing through a purge control valve in consideration of a transportation delay time duration and a behavior of the evaporated fuel gas. An instructed injection amount determining section A10 calculates a purge correction amount based on the evaporated fuel gas concentration learning value and the estimated purge flow.

Abstract: A system for supplying fuel under pressure to an internal combustion engine, and to control fuel delivery to a fuel injection system in an internal combustion engine having a low pressure pump formed integrally as at least part of a main housing of a vapor separator assembly. The low pressure pump lifts fuel into a cavity of a reservoir, which is drawn from a high pressure pump into the internal combustion engine. Due to the integrated nature of the low pressure pump, leak paths and assembly costs are reduced.

Abstract: A fuel vapor storage and recovery system of an internal combustion engine includes a fuel tank and a filter device arranged in a tank venting line. A heat exchanger is disposed in the tank venting line. The heat exchanger cools the fuel vapors flowing from the fuel tank to the filter device and heats air that is aspirated for scavenging the filter device.

Abstract: A fuel supply system for a boat prevents deterioration in engine startability and includes a vapor separator tank arranged to contain fuel at an inner fuel level “P” at a predetermined height, an injector arranged to supply fuel to an engine, and a high-pressure fuel pump that is disposed outside the vapor separator tank and that is arranged to supply the fuel reserved in the vapor separator tank to the injector. The high-pressure fuel pump includes a negative pressure generating portion arranged to generate negative pressure when the high-pressure fuel pump draws fuel, the negative pressure generating portion being positioned lower than the fuel level “P” in the vapor separator tank.

Abstract: A high-pressure fuel supply circuit, which supplies fuel in a fuel tank to injectors of an internal combustion engine, may includes a fuel pump that is employed so as to feed the fuel in the fuel tank with pressure to the injector, wherein one or more fuel pumps may be employed so as to improve a compression ratio of the fuel; a separator provided with a selective check valve so as to separate air from the fuel supplied by the fuel pump; and an injection pump receiving the fuel from the separator, compressing it, and feeding it with pressure to the injector.

Abstract: A relief valve is provided for use with a fuel system. The relief valve may have a housing forming an inlet, an outlet, and a central bore fluidly connecting the inlet to the outlet. The relief valve may also have a valve element disposed within the central bore of the housing and being configured to move between a flow-passing position and a flow-blocking position. The valve element may have a passageway continuously communicating the inlet of the housing with the outlet of the housing. The relief valve may also have a resilient member situated to bias the valve element toward the flow-blocking position.

Abstract: A device for a venting circuit of a liquid tank provided with a canister and a filling tube including a filling head, this device comprising: a) a control chamber that communicates with: the canister via a main orifice and a smaller-flow-area secondary orifice, both terminating in a ventilation line leading to the canister; the interior of the tank via the venting circuit; and the filling head via a pressure-equalizing line; b) a closure member that is: provided with an opening therethrough which brings the venting circuit into communication with the pressure-equalizing line; able to move in the control chamber between an operating position with the main orifice closed off by gravity and the secondary orifice left open, and a filling position with both orifices left open; and shaped to sealingly conform to at least a control chamber part that includes the main orifice.

Abstract: A hydrocarbon vapour filter system for capturing vapour released from a fuel tank. The system contains a vapour line in vapour-tight communication with the fuel tank, having a vapour capture segment for capturing fuel vapour, and in the preferred embodiment a purging stage releasing the fuel vapour. During engine operation captured fuel vapour can be released from the vapour capture line into air drawn into the engine intake manifold.

Abstract: A fuel supply system that includes a fuel pump, a jet pump, a first device and a second device. The fuel pump has a first port, a second port and a third port. Each of the first and second ports is configured to discharge a pressurized fuel. The third port is configured to discharge a fuel vapor that may be produced within the fuel pump. The first port is coupled to an engine via a fuel supply passage. The first device is coupled between the second port and the jet pump and is operable to permit and prevent the supply of the pressurized fuel to the jet pump. The second device is coupled to the third port and is operable to permit and prevent the discharge of the fuel vapor to the outside of the second device.

Abstract: A system for a vehicle includes an initialization module and a purge control module. The initialization module generates an initialization signal based on a crankshaft speed signal and/or a fuel rail pressure signal. The initialization module also generates the initialization signal based on an initial purge value and an assembly-line monitoring value. The purge control module generates a purge signal to purge air from a fuel injection system of an engine. The purge signal is generated when the crankshaft speed signal indicates that a crankshaft of the engine is stationary and/or the fuel rail pressure signal indicates that a fuel rail pressure is less than a predetermined value. The purge signal is also generated based on the initialization signal.

Abstract: An on-board refueling vapor recovery system includes a shutoff mechanism that closes a first vapor path between the fuel tank and the filler cup when liquid fuel in the tank reaches a predetermined level and a vent line closure that closes a second vapor path between the canister and the filler cup, wherein closure of the first vapor path and the second vapor path reduces pressure in the filler cup to induce shutoff of a fuel nozzle.

Abstract: A fuel tank has a tank body and a fuel inlet projecting upwardly from the tank body. The fuel tank includes a cylindrical member extending into the tank body, a canister, and a discharging passage in communication with the canister housing an adsorbent for absorbing fuel vapor from the fuel tank. A space between an outer circumferential surface of the cylindrical member and an inner circumferential surface of the fuel inlet is hermetically sealed by a seal. The cylindrical member has a passage for communicating an inside of the cylindrical member with a portion of an outside of the cylindrical member that is lower than the hermetically sealed space. The passage allows air in the tank body to enter the fuel inlet when fuel overflows from the fuel inlet, thereby inhibiting flow of fuel into the canister through the discharging passage.

Abstract: Systems and methods for an engine are described. In one example, a system may include a variable venturi coupled in an intake of the engine; an exhaust gas recirculation system having an exhaust gas recirculation flow path, the exhaust gas recirculation flow path coupled to the variable venturi; and a vacuum-utilizing device or system coupled to the variable venturi. In another example, a method may include coordinating adjustment of an exhaust gas recirculation valve coupled to the exhaust gas recirculation system, a fuel vapor purging valve coupled to the fuel vapor purging system, and the variable venturi in response to operating conditions.

Abstract: An evaporative emissions system may include a first passage selectively providing fluid communication between a fuel vapor region of a vehicle fuel reservoir and an engine air intake system, a second passage in fluid communication with the fuel vapor region and ambient air, and a filter assembly. The filter assembly may be impermeable to at least one of oxygen and hydrocarbons and may be located in the second passage between the fuel vapor region and ambient air. The filter assembly may prevent the at least one of oxygen and hydrocarbons from traveling between the fuel vapor region and ambient air.