Methods and systems are provided for indicating whether a canister purge valve in a vehicle evaporative emissions control system is degraded. In one example, an air intake system hydrocarbon (AIS HC) trap temperature may be monitored during a refueling event, and responsive to an indication that the AIS HC trap temperature change is greater than a predetermined threshold, it may be indicated that the canister purge valve is degraded. In this way, diagnosis of whether a vehicle canister purge valve is degraded may be indicated without the use of engine manifold vacuum, and may be advantageous for vehicles configured to operate for significant amounts of time without engine operation, or without intake manifold vacuum.

A fill limit vent valve for a fuel system includes a housing assembly, an outlet port and a flow dam. The housing assembly has a main housing including a cylindrical body and an upper housing portion. The upper housing portion has a lower wall that defines an orifice and an outer cylindrical wall that defines an upper housing chamber. The outlet port is formed on the main housing and fluidly communicates fuel vapor out of the fill limit valve. The orifice is offset from a centerpoint of the lower wall in a direction away from the outlet port. The flow dam extends from the lower wall into the upper housing chamber and connects on opposite ends to the outer cylindrical wall. The flow dam and upper housing chamber cooperating to form a liquid trap that mitigates the possibility of liquid fuel from reaching the outlet port from the orifice.

An evaporative emissions control system includes a first vent valve configured to selectively open and close a first vent, a second vent valve configured to selectively open and close a second vent, a fuel level sensor configured to sense a fuel level in the fuel tank, a pressure sensor configured to sense a pressure in the fuel tank, an accelerometer configured to measure an acceleration of the vehicle, and a controller configured to regulate operation of the first and second vent valves to provide pressure relief for the fuel tank. The controller is programmed to determine if a refueling event is occurring based one signals indicating the fuel level is increasing, the pressure in the fuel tank is increasing, and the vehicle is not moving, and open at least one of the first and second vent valves based on determining the refueling event is occurring.

Methods and systems are provided for vehicle fuel tanks including multiple reservoirs. In one example, a method may include opening a canister purge valve of a fuel system responsive to a fuel level of a fuel tank transitioning above a first threshold fuel level, and closing the canister purge valve after flowing a pre-determined amount of fuel to the fuel tank while the canister purge valve is open.

A fuel storage device includes a fuel tank, a circulation passage, a canister, a vapor passage, and an adjuster. The fuel tank is configured to store fuel. The circulation passage fluidly connects the fuel tank and a vicinity of a fuel supply port. The canister is configured to recover gas generated in the fuel tank. The vapor passage fluidly connects the fuel tank and the canister. The adjuster is configured to adjust a circulation flow rate of the gas flowing through the circulation passage in supply of the fuel, using a negative pressure.

A fluid tank that includes a housing. The housing includes a bottom wall, a top wall, and a side wall. The side wall couples the bottom wall to the top wall to define a cavity that receives and houses a liquid. A conduit guides liquid from a fluid source into the cavity. The conduit defines an inlet and an outlet. The outlet couples to the side wall. A vent coupled to the housing and to the conduit. The vent defines a vent inlet coupled to the housing and a vent outlet coupled to the conduit. The vent discharges gas from the housing into the conduit.

A fuel system, a method of fueling a vehicle, and a vehicle are provided. The fuel system has a recirculation line connecting a fuel tank to a fuel fill inlet. An ejector is positioned within the recirculation line, and a valve is positioned within a drain line fluidly connecting the ejector to the fuel tank. A pressure sensor is positioned to measure a pressure associated with the drain line between the ejector and the valve. A controller is in communication with the pressure sensor, and the controller configured to, in response to initiation of a refueling event, determine a state of the valve based on the pressure.

A full charge notification device of a urea water tank for a vehicle is provided. The device is configured to generate a predetermined sound when urea water is normally injected into the urea water tank before a full state, to provide a notification to a user of a full state of the urea water tank through non-generation of the sound.

There is provided a check valve for a fuel tank, including a cover to be welded to the fuel tank, a case welded to the cover and having a discharge port configured to discharge fuel into the fuel tank, and a valve body configured to open and close the discharge port. The cover includes a positioning portion on an outer circumferential surface. The case includes a vent hole which is arranged upward in a circumferential direction of the case when the check valve is mounted on the fuel tank, and a valve body supporting portion which supports the valve body inside the case. The valve body supporting portion includes a selecting portion for positioning the vent hole, which is provided on a discharge port side at a position away from the positioning portion by a predetermined angle in the circumferential direction of the case.

A fuel tank unit may include a fuel tank, a canister configured to adsorb and desorb vapor generated in the fuel tank, a vapor conduit communicating the fuel tank with the canister, and a full tank fuel level limiting valve device connected to a fuel tank-side end of the vapor conduit. The full tank fuel level limiting valve device includes a full tank fuel level limiting valve and an actuator. The full tank fuel level limiting valve includes a float that is configured to float due to a buoyancy force of fuel in the fuel tank so as to close the full tank fuel level limiting valve when the fuel tank is filled up. The actuator includes a valve closure prevention member that is configured to move and press the float when the actuator is activated, so as to prevent the float from moving in a valve closing direction.