This disclosure is directed to vehicle fuel fill control systems for anticipating vehicle refueling events in order to control the timing of fuel tank depressurization sequences. In a first embodiment, a global positioning system (GPS) is utilized to anticipate the vehicle refueling event prior to initializing the depressurization sequence. In another embodiment, a camera system is utilized to anticipate the refueling event prior to initializing the depressurization sequence. In yet another embodiment, both the GPS and the camera system may be utilized to anticipate the refueling event. By anticipating refueling events, customer wait time for gaining refueling access may be reduced.

Methods and systems are provided for reverse purging in a non-integrated refueling canister only system based on diurnal temperature variation. In one example, a method may include during a vehicle-off condition, in response to an estimated cooling of fuel in a fuel tank, unseal the fuel tank by pulsing a refueling valve (RV) to an open position. The cooling of the fuel may be estimated based on output of a first solar cell.

Methods and systems are provided for providing improving customer satisfaction during a vehicle fuel tank refueling event. A fuel system is configured with a three-way isolation valve and a four port canister. Fuel tank depressurization is expedited by directing fuel tank vapors to a dedicated depressurization port of the canister.

A fuel tank system controlled by a control module and constructed in accordance to one example of the present disclosure includes a saddle fuel tank, and a venting assembly. The saddle fuel tank has a first lobe and a second lobe extending on opposite ends of a recessed central portion. The venting assembly comprises a first vent line, a second vent line and a rotary actuator. The first vent line has a first vent port located in the first lobe of the saddle fuel tank near a top portion of the saddle fuel tank above the recessed central portion. The second vent line has a second vent port located in the second lobe of the saddle fuel tank near a top portion of the saddle fuel tank above the recessed central portion.

Methods and systems are provided for purging a fuel vapor storage canister in an evaporative emissions system of a vehicle. In one example, a method may include generating vacuum in a fuel tank fluidically coupled to the fuel vapor storage canister during an auto-stop of an engine while the engine spins down to rest, and purging vapors to an intake manifold of the engine during a subsequent restart of the engine. In this way, the fuel tank may be held at a vacuum while the engine is off, enabling more efficient purging of the fuel vapor storage canister when the engine is restarted.

This disclosure is directed to vehicle fuel fill control systems for anticipating vehicle refueling events in order to control the timing of fuel tank depressurization sequences. In a first embodiment, a global positioning system (GPS) is utilized to anticipate the vehicle refueling event prior to initializing the depressurization sequence. In another embodiment, a camera system is utilized to anticipate the refueling event prior to initializing the depressurization sequence. In yet another embodiment, both the GPS and the camera system may be utilized to anticipate the refueling event. By anticipating refueling events, customer wait time for gaining refueling access may be reduced.

Determining the thermodynamic state of fuel includes opening the venting connection to release the tank pressure while monitoring the derivative pressure (dP/dt), closing the venting connection when one of the following conditions is met, the derivative pressure (dP/dt) is lower than a predetermined threshold DP1 or the opening time t1 reaches a predetermined value, if the closing of the venting connection occurs when the opening time t1 reaches the said predetermined value, determining that the fuel is boiling and aborting the method if the closing of the venting connection occurs when the derivative pressure (dP/dt) is lower than the said threshold DP1, measuring an initial tank pressure at the closing of the venting connection, measuring the final tank pressure after a closure time t2, calculating the pressure variation (P/t2), comparing the pressure variation (P/t2) with a first threshold PV1, if the pressure is lower then aborting the method.

A fuel tank isolation valve (FTIV) is provided, configured for being disposed in fluid flow communication with a fuel tank and a carbon canister of a fuel system, the FTIV including an integrated controller and a solenoid coupled to a valve, the solenoid being movable between a normally closed position in which the valve is closed and prevents fluid communication through a first flowpath through the FTIV, and an open position in which the valve is open and allows for fluid communication through the first flowpath, the integrated controller being configured for generating actuation signals to the solenoid, responsive to parameter signals received from one or more sensors associated with the fuel tank. A sensing system for use with a fuel system is also provided, the sensing system including the FTIV and at least one such sensor. A fuel system is also provided, including a fuel tank and a carbon canister, and also including the sensing system for use therewith.

A fuel tank system constructed in accordance to one example of the present disclosure includes a saddle fuel tank, a control module, a first and second solenoid, and a first and second vent line. The saddle fuel tank can have a first lobe and a second lobe. The first vent line can have a first vent port located in the first lobe of the saddle fuel tank. The first solenoid is configured to open and close the first vent port. The second vent line can have a second vent port located in the second lobe of the saddle fuel tank. The second solenoid is configured to open and close the second vent port. The control module sends a signal to the first and second solenoids to close the first and second vents upon reaching a full fuel condition.

Methods and systems are provided for reducing degradation and issues related to noise, vibration and harshness (NVH) for a fuel tank pressure control valve configured to seal a fuel tank from atmosphere. In one example, a method may include depressurizing the fuel tank of a vehicle by duty cycling a tank pressure control valve and routing fuel vapors from the fuel tank to an engine, while controlling a timing of opening and closing events of the tank pressure control valve to coincide with pressure differences across the tank pressure control valve less than a threshold pressure difference in terms of pressure oscillations across the tank pressure control valve. In this way, higher loads and stress on the tank pressure control valve may be avoided, thus reducing degradation and NVH issues.