Methods and systems are provided for a fuel system. In one example, a fuel system includes a plurality of canisters with a fuel tank isolation valve (FTIV) configured to control a fluid coupling between each of the plurality of canisters and a fuel tank. The FTIV is actuated based on one or more of a fuel tank pressure and a load of each of the plurality of canisters.

The disclosure relates to a tank ventilation apparatus for a motor vehicle which has a scavenging line which is arranged between an activated-carbon container and an intake line of the motor vehicle and in which an electrically driven scavenging pump is arranged. Furthermore, an electrically controllable directional control valve is provided in the scavenging line between the activated-carbon container and the electrically driven scavenging pump.

The present disclosure relates to the field of automobile valve, specifically to a fuel tank isolation valve. Including: a separating valve main body, the separating valve main body is internally provided with a valve cavity, the valve cavity is internally provided with a clapboard; an electromagnetic valve, the electromagnetic valve is installed on the isolation valve main body, the electromagnetic valve comprises a movable plunger extending into the valve cavity, the front end of the movable plunger is provided with a plug, the plug is opposite to the clapboard, one side of the movable plunger far away from the clapboard is propped against with a first spring; further comprising: a temporary power-off pressure relief device, the temporary power-off pressure relief device comprises a limiting seat, a sliding seat and a conversion device, the sliding seat is set at the front end of the electromagnetic valve body, the limiting seat is set on the movable plunger; the limiting seat and the sliding seat are respectively provided with axially opposite locking projections and convex eaves; the conversion device is used for converting the axial driving force of the movable plunger to the limiting seat to drive the limiting seat to rotate in the circumferential direction in one way; one side of the convex eave is provided with a first sliding groove for containing the convex axial sliding of the lock. It can realize the function of temporary power-off and pressure relief.

Methods and systems are provided for performing a reverse purge of an evaporative emissions canister in a vehicle with a sealed variable volume fuel tank. In one example, a method may comprise in response to an ambient temperature reducing during a diurnal temperature cycle, and further in response to the EVAP canister loaded with fuel vapors above a threshold, closing a valve positioned at an atmospheric port of the fuel tank and opening a fuel tank isolation valve. In one example, the fuel tank isolation valve may be in fluid communication between the fuel tank and the EVAP canister. In this way, it is possible to convert a sealed variable volume fuel tank to a vented pressurized fuel tank and initiate a reverse purge during the cooldown hours of the diurnal temperature cycle.