Abstract: A vehicle method for barometric pressure identification, including adjusting engine operation responsive to barometric pressure, the barometric pressure based on a pressure change at a sector of the fuel system when the sector is sealed with the vehicle travelling. The method may utilize a pressure change at the sealed sector of the fuel system, such as a sealed fuel tank, to identify barometric pressure, even with the engine off for extended durations of vehicle travel. As such, in a hybrid-vehicle application, including during hill descents in which the engine is maintained off, barometric pressure can still be updated.

Abstract: A method for detecting blockage within a recirculation tube of the evaporative emission control system of a PHEV measures the rise in interior temperature of a canister of the EVAP system, during the process of refueling, and notes an initial state of loading of the canister before refueling, indicative of the amount of hydrocarbons contained within the canister It is inferred that the recirculation tube is operative reliably if the rise in canister temperature is below a pre-determined temperature value.

Abstract: A fuel system is provided, including a fuel tank isolation valve comprising an actuation coil and a latchable valve shaft at least partially disposed within the actuation coil. A controller may be configured to indicate a position of the valve shaft based on a measured current-voltage relationship between the first and second terminal wires during a condition in which the magnetic field generated by actuation coil current has a flux density below a threshold required to adjust a position of the latchable valve shaft. In this way, the position of the latchable valve shaft may be indicated without moving the valve shaft, and without requiring an dedicated valve position sensor.

Abstract: Systems are provided for a fuel system comprising an external refueling request switch accessible at or near a refueling door, thus enabling methods that may include initiating depressurization of a fuel tank responsive to an operator engaging the refueling request switch. The status of depressurization may be communicated to the operator via on one or more LED displays located either inside the refueling assembly or located at the refueling door. In this way, refueling requests may be initiated by a refueling operator, and by relaying the status of depressurization to the operator, any confusion on the part of the operator may be avoided.

Abstract: A method is provided, comprising indicating a fuel vapor canister load based on a steady-state pressure in a vapor recovery line during a refueling event; and adjusting a canister purging operation in response to the indicated fuel vapor canister load. Restrictions in the vapor recovery line may increase the rate of fuel vapor canister loading during a refueling event. In this way, an accurate canister load may be determined following a refueling event, and canister purging operations adjusted accordingly.

Abstract: A method is provided, comprising indicating a fuel vapor canister load based on a steady-state fuel vapor circulation rate in a vapor recovery line during a refueling event; and adjusting a canister purging operation in response to the indicated fuel vapor canister load. Restrictions in the vapor recovery line may increase the rate of fuel vapor canister loading during a refueling event. In this way, an accurate canister load may be determined following a refueling event, and canister purging operations adjusted accordingly.

Abstract: A method for a fuel system is provided, comprising adjusting a volume of a sealed fuel tank while maintaining spatial compartmentalization of bulk fuel within the sealed fuel tank, and indicating degradation of the sealed fuel tank based on a change in fuel tank pressure. In this way, the fuel tank may be tested for leaks without being unsealed, and without engaging the fuel pump or other elements of the fuel delivery system.

Abstract: A method is provided, comprising terminating a pressure rise portion of an engine-off natural vacuum test based on an initial rate of change of a fuel system pressure upon sealing a fuel system; and initiating a vacuum portion of the engine-off natural vacuum test responsive to suspending the pressure rise portion. The initial rate of change may indicate a likelihood of the pressure rise portion reaching a pressure rise threshold. In this way, the vacuum portion of the test may be initiated earlier, increasing the likelihood of a conclusive result being obtained during a test time limit.

Abstract: Systems and methods for operating a hybrid electric vehicle with a passive venturi pump are disclosed. In one example approach, a method comprises: during vehicle motion, passing air through a venturi coupled to the vehicle to generate vacuum; storing the generated in an accumulator; and, in response to a condition, discharging the stored vacuum to a vacuum consuming system of the vehicle.

Abstract: A method for operating a fuel system is disclosed. The method includes sequentially purging fuel vapors from each of a plurality of regions of a canister. Purging a region includes opening an air inlet valve associated with that region and maintaining air inlet valves associated with each other region closed to direct fuel vapors to at least one purge outlet.

Abstract: A method for a vehicle, comprising: depressurizing a fuel tank while restricting access to a fuel fill line responsive to receiving a refueling request from a refueling request module located external to a vehicle cabin; and allowing access to the fuel fill line responsive to the fuel tank pressure decreasing below a threshold. In this way, all of the steps of a refueling procedure can be carried out entirely outside of a vehicle.

Abstract: A vehicle method for barometric pressure identification, including adjusting engine operation responsive to barometric pressure, the barometric pressure based on a pressure change at a sector of the fuel system when the sector is sealed with the vehicle travelling. The method may utilize a pressure change at the sealed sector of the fuel system, such as a sealed fuel tank, to identify barometric pressure, even with the engine off for extended durations of vehicle travel. As such, in a hybrid-vehicle application, including during hill descents in which the engine is maintained off, barometric pressure can still be updated.

Abstract: A fuel tank for a hybrid vehicle is disclosed. In one example approach, a fuel tank for a vehicle comprises a wave catcher extending through an interior of the fuel tank and coupled to a front wall and a first side wall of the fuel tank.

Abstract: A distensible fuel tank included in a vehicle is provided. The distensible fuel tank includes a housing and a compliance structure coupled to the housing, the compliance structure including a base element coupled to a side of a structural element.

Abstract: A pet barrier includes a housing containing a barrier having a first end attached to a holding structure. The holding structure rotates with respect to the housing and the barrier is furled around the holding structure. The second end of the barrier is exposed from the housing and includes an elongated bar hook. The pet barrier also includes a tensioning mechanism including a spring assembly operably associated with the holding structure. An adjustment structure is provided for adjusting the tension of the spring assembly by rotational action and thereby adjusting tension in the barrier. To set the tension of the spring assembly, a brake is provided that locks the adjustment structure to with a portion of the housing and/or a portion fixed with respect to the housing. Constant retraction forces act upon the barrier as it is unfurled from around the holding structure.

Abstract: Methods and systems for cleaning a capless refueling system in a vehicle are disclosed. In one example approach, a method comprises, in response to a leak detected following a refueling event, cleaning the capless refueling system using engine vacuum.

Abstract: Methods and systems are provided for identifying leaks on each of a fuel tank and a canister side of a fuel system using a single leak check module. A position of a switching valve coupled in the vapor line of the fuel system is adjusted to selectively couple the leak check module to either the fuel tank or the canister. Leak is detected based on a change in pressure at a reference orifice of the leak check module following applying of vacuum from a vacuum pump.

Abstract: A method for purging fuel vapors, comprising: purging fuel tank vapors directly from a fuel tank to an engine intake, bypassing a canister, via a venturi, while drawing canister vapors via the venturi into the purged fuel tank vapors en route to the engine intake. In this way, fuel tank vapors may be used to enable purging of a fuel vapor canister, even under conditions where there is insufficient manifold vacuum to enable a canister purge routine. By increasing the frequency of purge opportunities, bleed emissions from a saturated canister may be reduced.

Abstract: A method for a fuel system, comprising: during a first condition, purging fuel vapor from a fuel vapor canister to a fuel vapor accumulator; and then during a second condition, evacuating fuel vapor from the fuel vapor accumulator to a fuel tank. The fuel vapor accumulator increases the volume of the fuel system, providing a temporary storage for desorbed fuel vapor. In this way, canister breakthrough of hydrocarbons can be mitigated, thereby reducing bleed emissions.

Abstract: A system for a vehicle, comprising: a tank pressure control valve coupled in a first conduit between a fuel tank and a fuel vapor canister; a refueling valve coupled in a second, different, conduit between the fuel tank and the fuel vapor canister, the second conduit in parallel to the first conduit. In this way, two smaller, less complex valves may be utilized to control fuel tank vapor purging and fuel tank depressurization during refueling. This in turn may lower system cost and increase system functionality.