A vehicle includes an engine, a fuel tank, a primary canister, a buffer canister, a purge valve, a check valve, and a controller. The fuel tank is configured to store fuel. The primary canister is configured to receive and store evaporated fuel from the fuel tank. The buffer canister is configured to receive and store the evaporated fuel from the fuel tank. The buffer canister is disposed between the primary canister and the engine. The purge valve is disposed between the buffer canister and the engine. The purge valve is configured to direct the evaporated fuel from the primary and buffer canisters to the engine when open. The check valve is disposed between the primary and buffer canisters and is configured to restrict backflow of the evaporated fuel from the buffer canister toward the primary canister. The controller is programmed to diagnose the operability of the check valve.

A dual purge system for a vehicle includes an ejector including a drive inlet section connected to a first end of a main body section, a suction inlet section connected to a first side of the main body section, an outlet section coupled to an intake passage section, a nozzle section, and a diffuser, wherein the diffuser communicates with internal passages of the main body section and the outlet section and has a larger passage cross-sectional area than a channel cross-sectional area of an outlet of the nozzle section, wherein a driving fluid flows through the drive inlet section, in response to a negative pressure being produced in the main body section by the driving fluid, the suction inlet section suctions a fuel evaporation gas from a canister, and the outlet section discharges the driving fluid and the fuel evaporation gas.

A fuel vapor storage canister including an integral fuel trap is provided. The fuel trap includes bifurcated chambers with the dual purpose of trapping liquid trace and attenuating noise entering the canister shell and tank line. The upper chamber includes a baffle to block and collect liquid trace, the liquid trace falling through an opening in a partition for collection in a fuel trace collector. The fuel trace collector is suitably positioned within the lower chamber, immediately beneath the opening, and includes a cavity and a venturi. The venturi creates a region of low pressure during purging, which evacuates the cavity by suction. The cavity optionally includes an activated carbon billet, which maintains the pressure level in the fuel vapor line above a predetermined minimum value and which aids in converting the liquid trace to fuel vapor as well as in further attenuating noise escaping into the tank line.

Methods and systems are provided for diagnosing a heating element coupled to a canister of an evaporative emissions control (EVAP) system. In one example, a method (or system) may include evacuating the canister at different temperature conditions, and diagnosing the heating element based on the different times taken to evacuate the canister at the different temperature conditions.

Sorbent material sheets provide for enhanced performance in vapor adsorbing applications over conventional canisters and other emissions control equipment. The sorbent material sheets can be formed as part of a small, lightweight canister, or can be integrated into a fuel tank. The sorbent material sheets can also be used as part of an onboard refueling vapor recovery system to control volatile organic compound emissions from fuel tanks of gasoline vehicles, such as automobiles.

Sorbent material sheets are wound around a center core of material that includes additional sorbent. This configuration further increases the packaging efficiency and performance of the sorbent material sheets as part of an overall housing or apparatus. In some embodiments, the sorbent material sheets are arranged in a stacked configuration. Configurations of the sorbent material sheets as part of a canister are also described.

A fuel tank system includes a fuel storage unit, a processing unit, and a control unit. The control unit performs a first failure diagnosis of diagnosing a failure of the fuel storage unit in a state where the sealing valve is closed. When the control unit diagnoses that the fuel storage unit is normal, the control unit performs a second failure diagnosis of diagnosing a failure of a purge valve and a bypass valve by causing a pressure generation unit to generate pressure in a state where the sealing valve is closed. When there is a possibility that the purge valve and the bypass valve are in closed-sticking, the control unit performs a third failure diagnosis of specifying a failure in any one of closed-sticking of the purge valve and closed-sticking of the bypass valve by opening the sealing valve.

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.

Methods and systems are presented for operating a refueling valve of an evaporative emissions system. The methods and systems may attempt to reactivate a refueling valve that has stuck due to the refueling valve being exposed to liquid fuel. In one example, a voltage that is applied to the refueling valve may be increased to reactivate the refueling valve.

A method of controlling an evaporative emissions system for a vehicle is provided. A fuel system for a vehicle and a vehicle are also provided. A signal indicative of an entry condition associated with a secondary air flow path for a purge of an evaporative emissions canister is received. A filter is decoupled from a port of the evaporative emissions canister in response to receiving the signal and prior to the evaporative emissions canister purge. The evaporative emissions canister is purged by flowing atmospheric air into the port and through the evaporative emissions canister while the filter is decoupled from the port. The filter is coupled to the port of the evaporative emissions canister after purging the canister.