A module (49, 149, 249) for use in a vehicle fuel system, said module comprising a housing (7) having a first port (9), a second port (41) and a passage (57) between the first port and the second port; a closure body (11) that is moveably arranged in said housing; wherein said closure body is configured for closing the passage between the first port and the second port in a first position of the closure body and for allowing access to the passage in a second position of the closure body; and a pump (13) that is integrated in said housing (7), wherein said pump (13) communicates with the first port (9) and is configured for pumping fluid into or out of the first port (9) while the closure body (11) is in the first position, characterized in that the module (49, 149) further comprises a motor (15) and a closure body actuator (67) configured for positioning the closure body (11, 111) in at least the first position and the second position, wherein said closure body actuator is driven by said motor (15), and said motor is configured for driving the pump (13) while the closure body is in the first position.

Methods and systems are provided for regulating evaporative emissions from a fuel system. In one example, a method may comprise spinning an engine unfueled responsive to a hydrocarbon concentration at a fresh air end of a fuel vapor canister increasing above a first threshold. The method may comprise spinning the engine to pull hydrocarbons away until a hydrocarbon concentration at a purge end of the fuel vapor canister, opposite the fresh air end, increases above a second threshold.

An evaporative emission control system for a vehicle includes an engine, a fuel tank connected to the engine and a reversible purge pump connected between the fuel tank and the engine. Fuel vapor generated in the fuel tank is supplied to the engine. The purge pump is operable in a first direction to supply the fuel vapor from the fuel tank to the engine and a second direction to supply air to the fuel tank. A purge control valve is connected between the reversible purge pump and the engine to control a flow of the fuel vapor to the engine.

A pressure sensor for an evaporated fuel leak detector is used for checking airtightness in a fuel tank and a canister. The pressure sensor includes a sensor unit, a case, and a sealing resin. The sensor unit has a pressure receiving portion, a plurality of conduction terminals, and a mold resin portion. The case has a fluid flow path and a housing recess. A buffer recess having an outer shape larger than the outer shape of a pressure receiving surface is formed at a pressure receiving side L1 of the bottom of the housing recess. Further, a protruding cylinder portion protruding into the buffer recess toward a back side L2 is formed at an outer edge of an opening end portion of the fluid flow path on the back side L2.

A pressure sensor for an evaporated fuel leak detector is used for checking a leak in a fuel tank and a canister. The pressure sensor includes a sensor unit, a case, and a sealing resin. The sensor unit includes a pressure receiving portion for detecting a pressure of a fluid applied to a pressure receiving surface, and a mold resin portion covering a surface of the pressure receiving portion except for the pressure receiving surface. The case has a fluid flow path for introducing the fluid to the pressure receiving surface, and a housing recess in which the sensor unit is accommodated. The sealing resin is arranged in the housing recess, to at least cover a back surface of the mold resin portion located on an opposite side of the pressure receiving surface.

A pressure sensor for an evaporated fuel leak detector is used for checking a leak in a fuel tank and a canister. The pressure sensor includes a sensor unit, a case, and a sealing resin. The sensor unit has a pressure receiving portion, a plurality of conduction terminals, and a mold resin portion. The case is provided with a fluid flow path and a housing recess. The case has an annular inner wall surface that defines the housing recess and surrounds a side surface of the mold resin portion. The inner wall surface of the case is provided with a stepped surface that is parallel to the pressure receiving surface or is inclined by an internal angle of less than 90° with respect to the pressure receiving surface, in a cross section along a direction perpendicular to the pressure receiving surface.

Disclosed is a method for diagnosing sealing in a fuel vapor recirculation system for an engine of a motor vehicle. An electronic module is integrated into the engine control unit that is woken up and placed on standby periodically while the engine is off, at the start and end of time intervals in order to perform a respective leak diagnosis, the fuel vapor temperature Tsys being estimated as a function of a time t ending at the start of each interval and starting when the engine is switched off according to the following equation, in which Tamb is the ambient temperature measured, Tsys0 is the fuel vapor temperature when the vehicle is switched off, and tsys is a system response time:

Tsys(t)=Tamb+(Tsys0−Tamb)e.sup.−t/tsys.

An evaporated fuel processing may include: a canister disposed on a purge passage; a control valve disposed on the purge passage between an intake passage and the canister and switching between communication and cutoff states, the communication state where the canister and the intake passage communicate through the purge passage, and the cutoff state where communication between the canister and the intake passage is cut off on the purge passage; a pressure detector detecting a pressure in the purge passage on a canister side relative to the control valve; and a determining unit determining whether clogging is occurring in the purge passage between the control valve and the intake passage by using a difference between a pressure under the communication state and a pressure under the cutoff state that are detected by the pressure detector while the control valve repeatedly switches between the communication state and the cutoff state.

A tank venting system (14) for a motor vehicle (10) has a filter (16) to filter a venting gas (15) of a fuel tank (12) of the motor vehicle (10), a pump (25) to generate a flushing air stream (29) in order to flush the filter (16), and a control unit (30) that, for purposes of performing a leak test, is configured to detect a pressure signal (34) that is dependent on the gas pressure (P) present in the fuel tank (12) and to check whether the pressure signal (34) meets a prescribed leakage criterion (33). The pump (25) is fluidically interconnected between the filter (16) and a shut-off valve (26), whereby the shut-off valve (26) is configured to fluidically couple the pump (25) to an inlet site (27) of a fresh air system (19) of an internal combustion engine (11) of the motor vehicle (10), and whereby the control unit (30) is configured to operate the pump (25) for flushing the filter (16) as well as for performing the leak test.

Methods and systems are provided for conducting vehicle fuel system and/or evaporative emissions system diagnostics, where the diagnostics rely on a positive pressure with respect to atmospheric pressure. In one example, a method comprises activating an electric compressor positioned in an intake of an engine configured to receive purge gasses from the evaporative emissions system under boosted engine operation and natural engine operation, to direct a positive pressure with respect to atmospheric pressure to the fuel system and/or evaporative emission system to conduct said diagnostic. In this way, diagnostics that rely on positive pressure with respect to atmospheric pressure may be conducted in vehicles with a dual-path purge system, without introduction of a pump in the evaporative emissions system.