An evaporated fuel processing device configured to adsorb evaporated fuel in a fuel tank to a canister and to feed the adsorbed evaporated fuel to an engine. The device includes an inner pressure sensor configured to detect a pressure in an interior space of the fuel tank, a valve-opening start position determination means configured to change the stroke amount of a flow control valve from an initial condition and to determine a valve-opening start position of the flow control valve based on a requirement that a range of variation of the inner pressure is equal to or greater than a predetermined value, a learning means configured to store the valve-opening start position, and a prohibition means configured to prohibit the valve-opening start position determination means from determining the valve-opening start position when the inner pressure falls within a predetermined pressure range relative to the atmospheric pressure.

An evaporated fuel processing device utilizing a flow rate control valve as a valve positioned in a passage connecting a fuel tank with a canister. The device includes: a valve opening means for opening the flow rate control valve at a constant speed; an internal pressure sensor; a valve opening start position detecting means for acquiring a second derivative value of the internal pressure after a valve opening motion of the flow rate control valve has started and for detecting a valve opening start position of the flow rate control valve based on the second derivative value; a learning means for storing the valve opening start position; and a valve opening speed change means for changing a valve opening speed of the valve opening means based on a variation speed of the internal pressure before the valve opening motion of the flow rate control valve has started.

A tank ventilation valve has a housing (21), a closing member (4), a sealing seat (5) and a first space (17). A second space (18) is connected to the first space (17) via a control opening (19) that surrounds the sealing seat (5). A spring (6) pretensions the closing member (4) against the sealing seat (5) and closes the control opening (19). The closing member (4) opens as a function of a pressure difference between the first and second spaces (17, 18). The opened closing member (4) opens the control opening (19) so that the first space (17) is connected to a first line (2) connects to fresh air. The second space (18) is connected to a second line (3) that is attachable to a filter. Structure is provided to exert a further negative pressure on the closing member (4) to move the closing member (4) into the open position.

A fuel system is provided, including a fuel tank isolation valve comprising an actuation coil and a latchable valve shaft at least partially disposed within the actuation coil. A controller may be configured to indicate a position of the valve shaft based on a measured current-voltage relationship between the first and second terminal wires during a condition in which the magnetic field generated by actuation coil current has a flux density below a threshold required to adjust a position of the latchable valve shaft. In this way, the position of the latchable valve shaft may be indicated without moving the valve shaft, and without requiring a dedicated valve position sensor.

An engine control device configured to control an engine includes: a turbocharger having a turbine that is configured to be driven by exhaust gas of the engine; and a compressor coupled to the turbine and configured to compress fresh air; an air-bypass passage that communicates between an upstream and a downstream of the compressor; an air-bypass valve configured to open/close the passage; a canister configured to store evaporated fuel gas generated in a fuel tank; an ejector configured to suction the evaporated fuel gas from the canister by using differential pressure between the upstream and the downstream of the compressor and introduce the evaporated fuel gas to the upstream; a purge valve configured to open/close a purge passage through which the evaporated fuel gas is to delivered from the canister to the ejector; and a purge valve diagnosis unit configured to detect stuck open malfunction of the purge valve.

A vapor purge system for an engine, includes a purge valve having a housing including an input port in communication with a purge canister and including an output port in communication with an intake system component defining a first bore portion receiving the output port with a first seal member disposed therebetween. The intake system component includes a second bore portion receiving a housing portion of the purge valve with a second seal member disposed therebetween. The first and second seal members are spaced such that when the housing is pulled away from the intake system component and the first seal member is out of engagement between the first bore and the output port, the second seal member can remain in engagement so that a diagnostic module can diagnose detachment of the purge valve from the intake system before any hydrocarbon vapor can be released into the atmosphere.

An evaporated fuel processing device that includes a pressurizing pump configured to pressurize gas in the vapor passage downstream of the closing valve toward the closing valve; a first pressure sensor configured to detect a pressure in the fuel tank directly or indirectly, and/or a second pressure sensor configured to detect a pressure in the vapor passage downstream of the closing valve directly or indirectly. When the closing valve moves toward an open side in the closed state with the pressurizing pump pressurizing the gas in the vapor passage downstream of the closing valve toward the closing valve, the controller may specify a valve-opening-start position based on the pressure detected by the first pressure sensor and/or the pressure detected by the second pressure sensor, wherein the valve-opening-start position is a position where the closing valve transitions from the closed state to the opened state.

A method is provided, comprising indicating a fuel vapor canister load based on a steady-state pressure in a vapor recovery line during a refueling event; and adjusting a canister purging operation in response to the indicated fuel vapor canister load. Restrictions in the vapor recovery line may increase the rate of fuel vapor canister loading during a refueling event. In this way, an accurate canister load may be determined following a refueling event, and canister purging operations adjusted accordingly.

A dual purge device for a vehicle includes a boost pressure introducing port and a fuel evaporation gas introducing port of an ejector that are directly mounted on an ejector mounting part formed on an intake manifold, and a first purge line connecting a purge valve to an intake manifold introducing pipe, respectively, without requiring a hose. By not using the hose or a quick connector, it is possible to simplify a structure of the dual purge device, and to integrally package the intake manifold, the purge valve, and the ejector, thereby simplifying delivery and assembly.

A fuel tank isolation solenoid valve for a vehicle includes: a plunger disposed in the isolation solenoid valve to be vertically moved and has first vent holes for releasing overpressure or over-negative pressure; a valve body disposed in the isolation solenoid valve to be vertically moved and has second vent holes for releasing overpressure or over-negative pressure.