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.

Disclosed is a method for detecting pinching or twisting of a discharge pipe connecting a fuel tank and an absorbent filter of an evaporation system of a motor vehicle. The method includes the steps, with the valve being initially in its closed position, of moving the valve by the gases circulating in the absorbent filter, of measuring, in the absence of control of the solenoid, the voltage generated at the terminals of the solenoid by the movement of the valve, and of detecting pinching or twisting of the discharge pipe when the voltage measured is between a first predetermined threshold and a second predetermined threshold.

A fuel tank system constructed in accordance to one example of the present disclosure includes a fuel tank and an evaporative emissions control system. The evaporative emissions control system is configured to recapture and recycle emitted fuel vapor. The evaporative emissions control system includes a liquid trap, a first device, a second device, a control module and a G-sensor. The first device is configured to selectively open and close a first vent. The second device is configured to selectively open and close a second vent. The control module regulates operation of the first and second devices to provide over-pressure and vacuum relief for the fuel tank. The G-sensor provides a signal to the control module based on a measured acceleration.

In a method for operating a tank device of a motor vehicle, with the tank device having a tank and a tank ventilation device with at least one switching valve, an excitation current can be applied to the switching valve, and the switching valve opens only when the excitation current exceeds an excitation current threshold over a certain period of time. Provision is hereby made to apply an excitation current which is greater than the excitation current threshold, at least temporarily, in a first mode of operation to the switching valve for heating purposes, also when ventilation of the tank is not governed by a control unit of the tank device.

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.

An evaporative emissions control system includes a first vent valve configured to selectively open and close a first vent, a second vent valve configured to selectively open and close a second vent, a fuel level sensor configured to sense a fuel level in the fuel tank, a pressure sensor configured to sense a pressure in the fuel tank, an accelerometer configured to measure an acceleration of the vehicle, and a controller configured to regulate operation of the first and second vent valves to provide pressure relief for the fuel tank. The controller is programmed to determine if a refueling event is occurring based one signals indicating the fuel level is increasing, the pressure in the fuel tank is increasing, and the vehicle is not moving, and open at least one of the first and second vent valves based on determining the refueling event is occurring.

A pressure relief valve (10) is provided for controlling fluid flow between a first fluid path (12a) and a second fluid path (12b). The pressure relief valve includes a housing (14), a diaphragm member (24) movably affixed within the housing and having a fluid port (18), a first biasing member (20) for urging the diaphragm member in a first direction, and a sealing member (26) movably mounted in the housing and configured for reversibly sealing the fluid port (18). When a pressure at the second fluid path (12b) exceeds a first predetermined threshold the diaphragm member (24) is pushed against the first biasing member (20), and the sealing member (26) is initially urged towards the fluid port (18) and subsequently becomes disengaged with the fluid port, allowing fluid communication between the second fluid path (12b) and the first fluid path (12a) via the fluid port. When the pressure at the second fluid path (12b) decreases below a second predetermined threshold, the sealing member (26) becomes disengaged from the diaphragm member (24), allowing fluid communication between the first fluid path and the second fluid path via the fluid port. A valve assembly including the pressure release valve (10) and an externally actuated valve (60) is also provided.

Methods and systems for controlling and reducing current consumption of a vapor blocking valve are disclosed. In one example, current supplied to the vapor blocking valve is adjusted proportionately to fuel tank pressure to compensate for fuel tank pressure acting on the vapor blocking valve. Vapor blocking valve current is adjusted to reduce current consumption.

An evaporated fuel processing device includes a flow control valve that is used as a valve to be installed in a pathway connecting a canister and a fuel tank. The device includes an inner pressure sensor configured to detect a pressure in an interior space of the fuel tank as an inner pressure, a valve-opening start position determination means configured to calculate a second order differential value of the inner pressure after a valve opening operation of the flow control valve is started and to determine a valve opening position of the flow control valve as a valve-opening start position when the second order differential value is equal to or greater than a first predetermined value, and a learning means configured to store the valve-opening start position as a learned value that is used when a valve-opening control of the flow control valve is performed.

A fueling system for an engine includes a fuel tank, a controller, a fuel nozzle receptacle connected to the fuel tank, the fuel nozzle receptacle including a receptacle sensor configured to send a signal to the contoller indicative of whether a fuel nozzle of a fuel dispenser is received in the fuel nozzle receptacle, and an electric fill slop valve between the fuel tank and the fuel nozzle receptacle, the electric fill stop valve being, configured to be controlled to open and close in response to a signal from the controller. The controller can be configured to receive at least one of (a) a signal whether a fuel nozzle of a fuel dispenser is received in a fuel nozzle receptacle connected to the fuel tank, and (b) a signal whether a fuel level of the fuel tank is full, and to control the electric fill stop valve to close when a signal is sent to the controller that at least one of (a) the fuel nozzle is not received in the fuel nozzle receptacle when the controller is configured to receive the signal whether the fuel nozzle of a fuel dispenser is received in the fuel nozzle receptacle, and (b) the fuel level of the fuel tank is full when the controller is configured to receive the signal whether the fuel level of the fuel tank is full.