An evaporative system is for an internal combustion engine. The internal combustion engine has an intake pipe equipped with a supercharger to pressurize intake air. The evaporative system includes an ejector, an ejector passage, and a pressure sensor. The ejector is to draw intake airflow from a downstream of the supercharger to an upstream of the supercharger to cause a negative pressure to draw fuel vapor into the upstream of the supercharger. The ejector passage is branched from the downstream of the supercharger and is returned through the ejector to the upstream of the supercharger. The pressure sensor is communicated with the ejector passage to detect pressure in the ejector passage.

A valve assembly for an air flow system, where the air flow system has a turbocharger unit and a venturi valve member for receiving a portion of the pressurized air from the turbocharger unit, and generating back pressure. The valve assembly includes a bypass switching valve and a bypass check valve. During a first mode of operation, the valve assembly is exposed to vacuum pressure, and the bypass check valve is exposed to the vacuum pressure such that the bypass check valve is placed in a closed position. During a second mode of operation the turbocharger unit is activated, pressurized air flows through the bypass switching valve, and places the bypass check valve in an open position, and the back pressure generated by the venturi valve member and the pressurized air from the turbocharger unit creates a pressure differential in the bypass check valve.

A vehicle fuel system includes a vapor recovery canister containing a primary carbon bed and a secondary carbon bed. Each carbon bed is configured to capture hydrocarbon material associated with fuel vapor discharged from a vehicle fuel tank.

A fuel vapor processing apparatus may include a diaphragm valve disposed in a vapor path communicating between a fuel tank and a canister. The diaphragm valve may include a valve chamber, a backpressure chamber, a diaphragm partitioning the valve chamber and the backpressure chamber from each other; and a valve member attached to the diaphragm. The backpressure chamber is not directly opened to an outside of the diaphragm valve. A control valve device may control a pressure within the backpressure chamber of the diaphragm valve.

An evaporated fuel processing device has a canister, a vapor passage, a purge passage, a shutoff valve, a storage device and a control device. The canister includes an adsorbent material that adsorbs evaporated fuel generated in a fuel tank. The vapor passage connects the canister and the fuel tank. The purge passage connects the canister and an intake passage of an engine. The shutoff valve is provided in the vapor passage, and adjusts flow rate of gas flowing through the vapor passage. The storage device stores in advance a reference value for the shutoff valve corresponding to internal pressure of the fuel tank. The shutoff valve is controlled based on the reference value, which is obtained from the internal pressure of the fuel tank, and pressure release control is performed on the fuel tank.

A processor may perform a purging process, which may introduce fuel vapor adsorbed by a canister into an intake passage. The processor may identify clogging of a purge passage based on a decrease amount of the pressure in the canister that results from execution of the purging process. The processor may open an isolation valve when the pressure in a fuel tank is less than or equal to a first pressure, which is less than an atmospheric pressure, and close the isolation valve when the pressure in the fuel tank is greater than or equal to a second pressure, which is greater than the first pressure and less than the atmospheric pressure. The processor may disable the purging process at least in a period from when the processor closes the isolation valve to when a prescribed time has elapsed from the closing of the isolation valve.

The invention relates to a system (1) and to a corresponding method for tank leakage diagnosis. The system (1) comprises a fuel tank (3), a pressure source (5, 9), and a pressure sensor (7). The pressure source (5, 9) is configured to increase the pressure in the fuel tank (3). The pressure sensor (7) is configured to detect the pressure progression at the fuel tank (3). The system (1) is configured to seal the fuel tank (3) in a gas-tight manner such that the fuel tank (3) can be used as a pressure store. Furthermore, the system (1) is configured to conclude, independently of a current operation of the pressure source (5, 9) based on the determined pressure progression at the fuel tank (3), that a leak is present.

Methods and systems are provided for a throttle plate and a vacuum consumption device. In one example, a method may include providing vacuum to a vacuum consumption device with a venturi passage inside a throttle.

Methods and systems are provided for a throttle plate and a vacuum consumption device. In one example, a method may include providing vacuum to a vacuum consumption device with a venturi passage inside a throttle.

A method for operating a switch valve which opens and closes a fluid line is disclosed. The switch valve is actuated by a pulse width modulated signal. The switch valve is actuated outside of the active operating time of the switch valve using PWM signals with an increasing or decreasing duty cycle. The duty cycle in which the switch valve is opened is determined, and the duty cycle corresponding to the opening time is then used to actuate the switch valve to open and close the switch valve during the active operating time of same. In this manner, the switch valve can be actuated in a particularly precise manner.