Methods and systems are provided for indication of a degradation in an EVAP and/or fuel system. In one example, a method for indication of a presence or absence of a degradation in a refueling system may include vacuum pull-down and pressure bleed-up tests being carried out based on a state of submersion of a spud valve in liquid fuel in a fuel tank.

An in-tank fuel pump assembly and mounting system is disclosed which may be configured for mounting inside a fuel tank. The assembly includes a pump housing, pump mounted to the housing, and pressure relief valve. The housing may comprise upper and lower pump housing units coupled together. The upper housing unit is configured for mounting to a tank opening, which in one implementation may be the fuel fill opening. The lower housing unit extends into the tank to approximately the bottom of the tank. A fuel fill fluid pathway is created through the housing for adding fuel to the tank while the pump assembly remains in situ. The upper housing unit may include a removable fuel cap. The pump housing may include an integral vapor trap.

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.

An evaporated fuel processing device includes a flow control valve that is used as a valve to be installed in a pathway connecting a canister and a fuel tank. The device includes an inner pressure sensor configured to detect a pressure in an interior space of the fuel tank as an inner pressure, a valve-opening start position determination means configured to calculate a second order differential value of the inner pressure after a valve opening operation of the flow control valve is started and to determine a valve opening position of the flow control valve as a valve-opening start position when the second order differential value is equal to or greater than a first predetermined value, and a learning means configured to store the valve-opening start position as a learned value that is used when a valve-opening control of the flow control valve is performed.

A fuel tank cap includes a casing; a main chamber disposed in the casing; a vapor vent channel disposed in the casing and communicating with the main chamber; annular partition walls disposed in the main chamber and configured to divide the main chamber into troughs surrounding a central tunnel, each partition wall including a cut so that the troughs and the tunnel are capable of communicating with each other via the cut; activated carbon filled in the troughs; and a permeable plug disposed in the tunnel, which is made by wrapping rust-resistant flexible wires so that a plurality of intercommunicated air gaps are formed among the flexible wires. The vapor vent channel includes the cuts, the troughs and the air gaps. The activated carbon captures fuel vapors and absorbs VOCs in the fuel vapors when the fuel vapors pass through the vapor vent channel.

The invention relates to a liquid/vapor separator (1) for a fuel tank for motor vehicles, comprising a housing (2) having a droplet collecting space (9) for fuel in vapor form. The housing (2) is provided with a connection cross section (4) which, in the installed position, opens into a space surrounded by a filler pipe of the motor vehicle. The liquid/vapor separator (1) comprises at least one first connection (6) for a refueling vent line of the fuel tank, said connection opening into the droplet collecting space (9), a second connection for a service vent line of the fuel tank, and a third connection (8) for a vent line leading to a fuel vapor filter. The liquid/vapor separator (1) according to the invention furthermore comprises at least one valve, which closes at least a service vent path (12) from the second connection to the fuel vapor filter during refueling of the motor vehicle, wherein the service vent path (12) is routed as a channel bypassing the droplet collecting space (9) into the connection cross section (4) of the housing (2).

A method for monitoring for a rupture in a storage element of a fuel tank system having a fuel tank includes: detecting, by a mass flow sensor, thermal conductivity of an unmoved air mass in a first line of the fuel tank system; and identifying a rupture in the storage element if the detecting by the mass flow sensor detects a change in the thermal conductivity of the unmoved air mass in the first line when a second valve is in a closed state and/or when an air pump is at a standstill.

A vaporized fuel processing apparatus in which, if an internal pressure of a fuel tank is high when refueling, a closing valve opens before a refueling cap opens, so that vaporized fuel is flown to a canister via a path with a float valve to lower the internal pressure of the tank. The apparatus includes a refueling switch for instructing a start of refueling to the fuel tank, an internal pressure sensor for detecting a space pressure inside the tank, and a closing valve control means for, if the refueling start signal is output from the refueling switch and the internal pressure of the fuel tank is higher than a set pressure, opening the closing valve within a range in which the float valve does not operate, and increasing the valve-opening speed of the closing valve in accordance with a reduction in the internal pressure of the fuel tank.

Methods and systems are provided for preventing fuel tank overfilling during refueling events, wherein overfilling of the fuel tank is prevented by delivering a pressure pulse to the fuel tank responsive to a fuel fill level reaching a predetermined threshold, or responsive to an attempt to add additional fuel subsequent to the fuel fill threshold being reached. In one example, an onboard pressure vessel is actively pressurized via an onboard pump, where the pressure may be actively released and routed to the fuel tank to induce an automatic shutoff of a refueling dispenser pump under predetermined conditions. In this way, automatic shutoffs of refueling dispenser pumps may be rapidly and reliably induced, thus preventing fuel tank overfilling, prolonging the lifetime of fuel vapor storage canisters, and reducing undesired evaporative emissions.

A two-stage switch valve includes a valve body slidable in a flow passage of a fluid, and a spring urging the valve body upstream. The valve body includes a valve element slidable in the flow passage, an upstream guide having a ring shape and being slidable in the flow passage, and legs connecting the valve element and the upstream guide. The upstream guide is located upstream of the valve element. The legs are inclined from an axial direction of the upstream guide and extend from the upstream guide toward a center of the valve element.