Abstract: Methods and systems are provided for diagnostics and subsequent cleaning of an ejector in a fuel vapor purge system of a vehicle with a boosted internal combustion engine. In one example, a method may include, in response to indication of blockage in a fuel vapor purge system, a purge system valve may be actuated to a position enabling routing of contaminants blocking the ejector to an engine intake manifold, thereby cleaning the ejector.

Abstract: Methods and systems are provided herein for a dust box cleanout routine of an evaporative emissions control (EVAP) system of a vehicle. In one example, a method is provided for an engine of a vehicle, comprising, during travel on an unpaved road, selectively discharging a dust box housed in a vent line of an evaporative emissions control (EVAP) system by opening a discharge valve of the dust box leading to atmosphere. In this way, an accumulation of dust on the air filter and in the dust box of the EVAP system may be reduced, thereby maintaining an efficiency of the EVAP system.

Abstract: Methods and systems are provided for diagnostics and subsequent cleaning of an ejector in a fuel vapor purge system of a vehicle with a boosted internal combustion engine. In one example, a method may include, in response to indication of blockage in a fuel vapor purge system, a purge system valve may be actuated to a position enabling routing of contaminants blocking the ejector to an engine intake manifold, thereby cleaning the ejector.

Abstract: Methods and systems are provided herein for a dust box cleanout routine of an evaporative emissions control (EVAP) system of a vehicle. In one example, a method is provided for an engine of a vehicle, comprising, during travel on an unpaved road, selectively discharging a dust box housed in a vent line of an evaporative emissions control (EVAP) system by opening a discharge valve of the dust box leading to atmosphere. In this way, an accumulation of dust on the air filter and in the dust box of the EVAP system may be reduced, thereby maintaining an efficiency of the EVAP system.

Abstract: A dual path fuel vapor purge system is disclosed for an engine having a turbocharger or a super. The purge system includes a canister configured to collect fuel vapor from a fuel tank. A canister purge valve is provided downstream from the canister. An ejector valve receives fuel vapors from the canister through the canister purge valve. A first vapor purge path directs the fuel vapor to an intake manifold of the engine. A second vapor purge path directs fuel vapor to an air induction system. A check valve downstream from the ejector valve receives the fuel vapor from the ejector and supplies the fuel vapor to the air induction system. Boost flow opens the check valve when the air induction system is in operation to boost the engine and closes the check valve when the engine is in operation with normal aspiration or when a leak is detected.

Abstract: Vapors in the fuel tank of a vehicle are collected in a carbon canister. An ejector or aspirator is used to purge the carbon canister in a pressure-charged engine in which a positive pressure exists in the intake. A compact ejector includes a substantially planar flange and a venturi tube coupled to the flange with a central axis of the venturi tube substantially parallel to the flange. By manufacturing the ejector in two pieces, dimensions within the ejector: throat, converging section, and diverging section, is more accurate than prior art manufacturing techniques thereby providing better flow characteristics throughout the boost range.

Abstract: Vapors in the fuel tank of a vehicle are collected in a carbon canister. An ejector or aspirator is used to purge the carbon canister in a pressure-charged engine in which a positive pressure exists in the intake. A compact ejector includes a substantially planar flange and a venturi tube coupled to the flange with a central axis of the venturi tube substantially parallel to the flange. By manufacturing the ejector in two pieces, dimensions within the ejector: throat, converging section, and diverging section, is more accurate than prior art manufacturing techniques thereby providing better flow characteristics throughout the boost range.

Abstract: Vapors in the fuel tank of a vehicle are collected in a carbon canister. An ejector or aspirator is used to purge the carbon canister in a pressure-charged engine in which a positive pressure exists in the intake. A compact ejector includes a substantially planar flange and a venturi tube coupled to the flange with a central axis of the venturi tube substantially parallel to the flange. By mounting the ejector on an intake component, having the venturi tube on the inside of the intake component, and having the venturi tube parallel to the flange yields a very compact package and protects the ejector from damage from other engine components.

Abstract: A method for operating a fuel vapor control system included in a vehicle having an internal combustion engine is provided. The method may include storing positive pressure or negative pressure in an isolated fuel tank, transferring at least a portion of the positive pressure or the negative pressure to an evaporation canister region, and determining degradation of the evaporation canister based on a pressure response of the evaporation canister region while the evaporation canister region is isolated from the fuel tank. In this way, it is possible to utilize pressure that may be passively generated in one portion of the system, even during shut-down engine operation, to verify the integrity of another portion of the system.

Abstract: A method for operating a fuel vapor control system included in a vehicle having an internal combustion engine is provided. The method may include storing positive pressure or negative pressure in an isolated fuel tank, transferring at least a portion of the positive pressure or the negative pressure to an evaporation canister region, and determining degradation of the evaporation canister based on a pressure response of the evaporation canister region while the evaporation canister region is isolated from the fuel tank. In this way, it is possible to utilize pressure that may be passively generated in one portion of the system, even during shut-down engine operation, to verify the integrity of another portion of the system.

Abstract: A purge control valve control system is provided for an internal combustion engine system, comprising: a voltage source having a positive potential and a negative potential; a purge control valve having a solenoid, such solenoid comprising an electrically inductive element, such inductive element having a first terminal coupled to the positive potential of the voltage source; a diode having an anode and a cathode. The control unit includes a transistor having: a control electrode fed by a train of pulses; a first electrode coupled to the negative potential of the voltage source; and a second electrode coupled to a second terminal of the inductive element and to the diode.

Abstract: Evaporative emissions management for a vehicle having a fuel tank and a low-vacuum internal combustion engine, including hybrid electric vehicles, include first and second canisters with the second canister disposed between the first canister and atmosphere. A refueling valve routes fuel vapors from the fuel storage tank through the first canister, and to the second canister when the first canister becomes saturated, during refueling. Other than during refueling, the refueling valve is closed to route fuel vapors around the first canister and directly into the second canister. First and second purge valves are controlled during canister regeneration or purging so air from atmosphere is routed primarily through the second canister to the engine to purge the second canister before the purge valves are operated to route air from atmosphere through both the second and first canisters to purge the first canister.

Abstract: Evaporative emissions management for a vehicle having a fuel tank and a low-vacuum internal combustion engine, including hybrid electric vehicles, include first and second canisters with the second canister disposed between the first canister and atmosphere. A refueling valve routes fuel vapors from the fuel storage tank through the first canister, and to the second canister when the first canister becomes saturated, during refueling. Other than during refueling, the refueling valve is closed to route fuel vapors around the first canister and directly into the second canister. First and second purge valves are controlled during canister regeneration or purging so air from atmosphere is routed primarily through the second canister to the engine to purge the second canister before the purge valves are operated to route air from atmosphere through both the second and first canisters to purge the first canister.