A vehicle includes a fuel tank, a primary canister, a secondary canister, a first valve, a second valve, a third valve, a heater, and a controller. The primary and secondary canisters are in fluid communication with the fuel tank and are configured to receive and store evaporated fuel from the fuel tank. The first valve is disposed between the fuel tank and the primary canister. The second valve is disposed between the secondary canister and ambient surroundings. The third valve is disposed between the primary canister and an engine. The heater is configured to heat the primary and secondary canisters. The controller is programmed to (i) activate the heater to heat the primary and secondary canisters and (ii) purge the evaporated fuel from the primary and secondary canisters after heating the primary and secondary canisters.

A fuel system comprising a fuel tank, a mixing volume configured to mix fuel vapor and air, the mixing volume comprising an outlet configured to be fluidly coupled to an engine, and a fuel vapor line configured to fluidly couple the fuel tank to the mixing volume.

A control valve is disposed on a vapor control system which controls vapor. A case and caps hold a diaphragm. The case and the diaphragm define a primary chamber. The caps and the diaphragm define a secondary chamber. The secondary chamber communicates to an inlet passage via a through hole formed as an orifice. An inlet pipe is arranged so that the inlet passage and the secondary chamber are adjacent each other by being separated by an outer wall. By employing this arrangement, the through hole can be formed without increasing a vapor permeable surface area. Since the through hole is not formed on the diaphragm, a stable open-and-close characteristic can be provided. The through hole may be formed by using a molding die for forming the inlet passage. Thereby, it is possible to improve productivity.

A vaporized fuel treating device having a canister that is configured to adsorb vaporized fuel in a fuel tank and to feed the adsorbed vaporized fuel to an engine may include a pressure sensor that is configured to periodically detect an inner pressure of the fuel tank, and a pressure sensor failure determination device that is configured to determine that the pressure sensor has failed when a change of the inner pressure detected by the pressure sensor in a unit of time is not less than a predetermined pressure value that is greater than a maximum value of possible pressure changes within the fuel tank.

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.

A method for diagnosing operation of a valve to purge a canister of an internal combustion engine, the method, carried out during a purge, including: a) detecting, at an instant to, that the purge valve is open; b) executing a forced closing of the valve at an instant t2; c) measuring a pressure P1m of the intake manifold and calculating a corresponding modelled pressure P1c, at an instant t1 between the instant t0 and the instant t2; d) measuring a pressure of the manifold P2m and calculating a corresponding modelled pressure P2c, at an instant t3 after the instant t2; e) calculating a deviation E1 between P1m and P1c and calculating a deviation E2 between P2m and P2c; f) calculating a criterion C=E1−E2; and g) diagnosing malfunction of the purge valve if the criterion C is lower than a predetermined threshold value Cs.

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.

Magnetic latching valves for a vehicle engine have a housing having a first port and a second port in controlled fluid communication with one another. The housing encloses a linearly translatable armature seated within a solenoid and connected to a primary poppet valve. The armature is movable between an open position and a closed position, respectively, after a pulse of voltage to the solenoid and is in an unpowered state thereafter. A permanent magnet is fixedly seated in a position to magnetically latch the armature in a fully open position. A spring is seated to bias the primary poppet valve closed when the armature is in the closed position. The spring has a spring rate that mechanically relieves pressure by opening the primary poppet valve a distance less than the fully open position when the spring force is exceeded, thereby also allowing flow in the primary flow direction.

Methods and systems for diagnosing operational status of a carbon filled canister heater are described. The methods and systems may include activating an evaporative emissions system heater, a pump, and a canister purge valve to determine if long chain hydrocarbons are released from a carbon filled canister. Release of long chain hydrocarbons from the carbon filled canister may be indicative of desired operation of a carbon filled canister heater.

A fuel-feeding device may include a fuel tank storing fuel therein, a fuel pump configured to feed the fuel in the fuel tank to an engine through a fuel-feeding conduit, an aspirator configured to generate a negative pressure therein using a flow of the fuel flowing through a branched conduit branched from the fuel-feeding conduit, a negative pressure sensor configured to detect the negative pressure generated by the aspirator, and a control device configured to control a revolution speed of the fuel pump. The control device is configured to determine a sign of vapor generation in the fuel stored in the fuel tank based on detection information of the negative pressure sensor.