Abstract: A system for a vehicle, comprising: a tank pressure control valve coupled in a first conduit between a fuel tank and a fuel vapor canister; a refueling valve coupled in a second, different, conduit between the fuel tank and the fuel vapor canister, the second conduit in parallel to the first conduit. In this way, two smaller, less complex valves may be utilized to control fuel tank vapor purging and fuel tank depressurization during refueling. This in turn may lower system cost and increase system functionality.

Abstract: Methods and systems are provided for purging a fuel vapor canister into an engine intake. A method comprises flowing fuel vapors from a fuel tank through a full length of the fuel vapor canister from a first input to a first output on a first opposite side from the first input. The adsorbed fuel vapors may be purged from the fuel vapor canister through a full width in the fuel vapor canister from a second input to a second output on a second opposite side from the second input.

Abstract: A method for a fuel system coupled to an engine comprising: under vacuum conditions, opening the fuel vapor canister purge valve, and generating pressure pulsations in a conduit coupled to the fuel vapor canister purge valve by opening and closing a fuel vapor canister vent valve one or more times while maintaining the fuel vapor canister purge valve open. In this way, contaminants and/or debris that may prevent the canister purge valve from closing completely may be dislodged and evacuated to the intake manifold.

Abstract: A system for a vehicle is provided herein. The system includes a fuel vapor canister comprising a shell, a compression plate within the shell and an end cap. The end cap includes a double sided spring interface and a double sided shell sealing surface having double sided identical grooves, only one of which is sealed to the shell. The system further includes a spring coupled to the compression plate and only one spring interface.

Abstract: Methods and systems for cleaning a capless refueling system in a vehicle are disclosed. In one example approach, a method comprises, in response to a leak detected following a refueling event, cleaning the capless refueling system using engine vacuum.

Abstract: A system for an engine, comprising: a fuel vapor canister coupled to a fuel tank; a thermal jacket comprising a phase-change material, the thermal jacket spatially sheathing the fuel vapor canister; and an engine coolant passage positioned to transfer thermal energy between engine coolant and the phase-change material. In this way, the phase-change material may buffer the temperature of the fuel vapor canister by absorbing heat generated during hydrocarbon adsorption, and returning the heat to the vapor canister during hydrocarbon desorption. By coupling the phase-change material to engine coolant, the thermal capacity of the thermal jacket can be increased, as heated coolant can thus transfer thermal energy to the phase-change material to replace the thermal energy transferred to the canister during hydrocarbon desorption.

Abstract: A system for an engine, comprising: a fuel tank; a thermal regulator comprising a phase-change material, the thermal regulator coupled to the fuel tank; and an engine coolant passage positioned to transfer thermal energy between engine coolant and the phase-change material. In this way, the temperature of the fuel tank may be managed passively by the phase-change material, and actively by engine coolant, thereby allowing heat energy to be shunted away from the fuel tank, cooling the fuel within the fuel tank, and reducing fuel vapor concentration, thus enabling a fuel vapor canister with a reduced size.

Abstract: A method for a vehicle, comprising: depressurizing a fuel tank while restricting access to a fuel fill line responsive to receiving a refueling request from a refueling request module located external to a vehicle cabin; and allowing access to the fuel fill line responsive to the fuel tank pressure decreasing below a threshold. In this way, all of the steps of a refueling procedure can be carried out entirely outside of a vehicle.

Abstract: A method for a fuel system, comprising: indicating a leak in a fuel tank following applying a vacuum to the fuel tank by running a vacuum pump in a first direction; then purging a fuel vapor canister to the fuel tank by running the vacuum pump in a second direction, opposite the first direction. In this way, the fuel vapor canister may be purged of its contents following a fuel system leak check. This may reduce bleed emissions while increasing the efficiency of the vehicle, as the engine does not need to be turned on in order to purge the canister.

Abstract: A method for a plug-in hybrid electric vehicle, comprising: during a first condition, including an engine-off condition and the plug-in hybrid electric vehicle coupled to an external power source; heating a fuel vapor canister based on a fuel tank vacuum; and opening a fuel tank isolation valve to draw heated vapors into a fuel tank. In this way, a passive purge operation may be executed, thereby purging the fuel vapor canister without forcing the engine to turn on. Thus, the vehicle may be operated at peak fuel economy without increasing emissions.

Abstract: A method for a vehicle fuel system, comprising: during an engine-off condition, including an ambient temperature within a threshold range, operating a cooling fan to increase a fuel tank vacuum; and indicating leaks in the vehicle fuel system based on the increased vacuum. In this way, an EONV test may be run at mild ambient temperatures which would not otherwise result in the development of adequate fuel tank vacuum to pass the EONV test.

Abstract: Systems and methods for improving fuel vapor purging for a vehicle are presented. In one example, a fuel vapor storage canister vent valve is housed in a fuel vapor storage canister for the purposes of heating contents of the fuel vapor storage canister and venting the fuel vapor storage canister to atmosphere.

Abstract: A method for operating a vehicle system is provided. The method includes monitoring a change in a temperature of the fuel vapor canister coupled to a fuel tank via a canister temperature sensor and adjusting operation of a fuel tank isolation valve based on the change in temperature of the fuel vapor canister.

Abstract: Methods and systems for fuel system leak detection are disclosed. In one example approach, a method comprises, during an engine-on condition, delivering fuel from a fuel tank to one or more cylinders of the engine while the fuel tank is sealed off from atmosphere, and indicating a leak based on pressure in the fuel tank. For example, a leak may be indicated in response to a pressure decrease in the fuel tank greater than an expected pressure decrease, where the expected pressure decrease is based on a fuel level in the fuel tank.

Abstract: Embodiments for monitoring fuel system degradation are provided. In one example, a method for a vehicle comprises evacuating fuel from a first fuel tank to a second fuel tank, and indicating fuel system degradation in response to a change in fuel system pressure following the evacuation of fuel. In this way, fuel system degradation may be indicated without use of a separate pressure building device.

Abstract: A method, comprising: indicating a leak of a first diameter on a canister side of a fuel system following applying a vacuum to the fuel system with a fuel tank isolation valve closed; and indicating a leak of a second diameter on a fuel tank side of the fuel system, based on a vacuum decay in an isolated fuel tank following applying a vacuum to the fuel system with the fuel tank isolation valve open. In this way, an evaporative leak check module with a single reference orifice may be used to determine leaks of multiple sizes in multiple sectors of a fuel system. This may allow current production models to meet more stringent emissions regulations in the future.

Abstract: A method, comprising: indicating leakage on a canister side of a fuel system based on a first fuel system pressure following applying a vacuum to the fuel system with a fuel tank isolation valve closed; and indicating leakage on a fuel tank side of the fuel system based on the first fuel system pressure and a second fuel system pressure following applying a vacuum to the fuel system with the fuel tank isolation valve open. In this way, an ELCM with a single reference orifice may be used to perform a leak test with two different thresholds for leak detection. This may allow vehicles currently in production to meet future emissions standards without costly upgrades to the ELCM.

Abstract: A method for a plug-in hybrid electric vehicle, comprising: during a first condition, including an engine-off condition and the plug-in hybrid electric vehicle coupled to an external power source; heating a fuel vapor canister based on a fuel tank vacuum; and opening a fuel tank isolation valve to draw heated vapors into a fuel tank. In this way, a passive purge operation may be executed, thereby purging the fuel vapor canister without forcing the engine to turn on. Thus, the vehicle may be operated at peak fuel economy without increasing emissions.

Abstract: A method for a plug-in hybrid electric vehicle, comprising: during a first condition, including an engine-off condition and the plug-in hybrid electric vehicle coupled to an external power source, cooling a vapor canister based on an ambient temperature. In this way, bleed emissions may be reduced in PHEVs during conditions when the vehicle is parked and recharging at a high ambient temperature.

Abstract: A method for a plug-in hybrid electric vehicle, comprising: during a first condition, including an engine-off condition and the plug-in hybrid electric vehicle coupled to an external power source, cooling a vapor canister based on an ambient temperature. In this way, bleed emissions may be reduced in PHEVs during conditions when the vehicle is parked and recharging at a high ambient temperature.