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.

Methods and systems are presented for diagnosing a breach of an evaporative emissions system. The methods and systems include repurposing a resonator as a vacuum reservoir to reduce a pressure of an evaporative emissions system so that it may be determined if there is or is not a breach of the evaporative emissions system.

A vehicle includes a fuel tank, a canister, a first valve, a second valve, a heater, and a controller. The fuel tank is configured to store fuel. The canister is in fluid communication with the fuel tank and is configured to receive and store evaporated fuel from the fuel tank. The first valve is disposed between the fuel tank and the canister. The second valve is disposed between the canister and ambient surroundings. The heater is disposed within the canister. The controller is programmed to, periodically initiate diagnostic tests that are configured to determine if the heater is operating properly, if the heater is unable to turn off, or if the heater is unable to turn on.

A fuel system, including a first pump, a second pump and a filter module. The filter module has a housing defining an interior, a filter received in the interior, a filter inlet through which fluid flows into the interior, a filter outlet from which fluid flows out of the interior, and a vent body received within the interior. The vent body has a passage and a vent orifice. The filter is arranged so that fluid that enters the filter inlet flows through the filter before flowing out of the filter outlet and the interior includes an upper portion arranged above a lower portion relative to the force of gravity, and the passage communicates with the filter outlet and with the lower portion of the interior and the vent orifice communicates with the passage and with the upper portion of the interior.

A leakage detector includes a pressure sensor for detecting the pressure in a detecting target area of the fuel vapor treatment system and a controller. The controller measures the pressure in the detecting target area at a certain point in time. The controller then determines whether the measured pressure satisfies a condition for leakage detection by a vapor pressure device. When the controller determines that the condition is satisfied, the controller selects the vapor pressure device. When the controller determines that the condition is not satisfied, the controller predicts the change in vapor pressure at a subsequent temperature based on a saturated vapor pressure characteristic of the fuel. If it is determined the pressure in the detecting target will satisfy a predetermined condition, the controller selects a pressure application device. If it is determined that the predetermined condition will be satisfied, the controller selects the vapor pressure device.

A vehicle includes a frame, a seat, a storage box, an engine body at least partially overlapping with the seat when seen from above, an intake system component, a fuel system component, an evaporative emission system, a pressure sensor, and at least one of an electric vent valve or an electric suction pump. At least one of the pressure sensor, the vent valve, or the suction pump is supported by at least one of a frame, a storage box, an engine body, an intake system component, or a fuel system component.

A vehicle includes a frame, a seat, a storage box, an engine body at least partially overlapping with the seat when seen from above, an intake system component, a fuel system component, an evaporative emission system, a pressure sensor, and at least one of an electric vent valve or an electric suction pump. At least one of the pressure sensor, the vent valve, or the suction pump is supported by at least one of a frame, a storage box, an engine body, an intake system component, or a fuel system component.

A straddled vehicle on which a part used for performing an inspection for a leak of gas from an evaporative emission system is mounted such that a weight balance of the straddled vehicle is maintained and mass concentrates includes a canister-integrated-leak-detection device that detects a leak of gas from an evaporative emission system. The canister-integrated-leak-detection device configured in a state where at least one of a vent valve or a suction pump is integrated with a canister is supported via a common attaching member to intersect with at least one of a virtual-left-right-center plane that includes a center in a left-right direction and is perpendicular to the left-right direction, a virtual-front-rear-center plane that includes a center in a front-rear direction and is perpendicular to the front-rear direction, or a virtual-up-down-center plane that includes a center in an up-down direction and is perpendicular to the up-down direction in the vehicle.

A gas-leak-detection device for detecting a gas leakage from an evaporative emission system includes an electric-wire-connection portion and a passage connection portion that are disposed to overlap with at least one of appearance components in a vehicle when the vehicle is seen in a viewing direction, and are disposed closer to the at least one appearance component than a center plane perpendicular to the viewing direction when the vehicle is in an upright state, the center plane being one of an imaginary-lateral-center plane that is an imaginary vertical plane perpendicular to the left-right direction, an imaginary-longitudinal-center plane that is an imaginary vertical plane including a center in the front-rear direction and being perpendicular to the front-rear direction, or an imaginary-vertical-center plane that is an imaginary horizontal plane including a center in the top-bottom direction and being perpendicular to the top-bottom direction.

A vehicle includes at least one of an electric vent valve configured to open and close an outside-air-introduction passage of a canister or an electric suction pump configured. to suck gas in a gas passage through which the gas flows. The canister and at least one of the vent valve or the suction pump are disposed such that at least one of a virtual-left-right-center plane that includes a center in a left-right direction and is perpendicular to the left-right direction, a virtual-front-rear-center plane that includes a center in a front-rear direction and is perpendicular to the front-rear direction, or a virtual-up-down-center plane that includes a center in an up-down direction and is perpendicular to the up-down direction is located between a gravity center of the canister and at least one of a gravity center of the vent valve or a gravity center of the suction pump.