Patent application number | Description | Published |
20130298879 | EVAPORATIVE EMISSION CONTROL - 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. | 11-14-2013 |
20140026865 | PASSIVE VENTURI PUMP FOR LEAK DIAGNOSTICS AND REFUELING - 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. | 01-30-2014 |
20140074385 | METHOD AND SYSTEM FOR FUEL VAPOR CONTROL - Methods and systems are provided for performing a vehicle-off fuel system leak test. A vehicle controller may be woken up after a vehicle has been in a key-off condition for a sufficient amount of time to monitor a fuel tank for pressure and temperature stabilization. If the pressure and temperature of the fuel tank is stable, a fuel pump may be operated to raise a fuel tank vapor pressure, and fuel system leaks are identified based on a rate of pressure decay from the fuel tank. | 03-13-2014 |
20140107906 | FUEL SYSTEM DEGRADATION TEST USING TWO FUEL TANKS - Embodiments for monitoring fuel system degradation are provided. In one example, a method for a vehicle comprises evacuating fuel from a first fuel tank to a second fuel tank, and indicating fuel system degradation in response to a change in fuel system pressure following the evacuation of fuel. In this way, fuel system degradation may be indicated without use of a separate pressure building device. | 04-17-2014 |
20140114550 | VEHICLE METHOD FOR BAROMETRIC PRESSURE IDENTIFICATION - 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. | 04-24-2014 |
20140130781 | FUEL SYSTEM DIAGNOSTICS - Methods and system are provided for distinguishing fuel tank vacuum generation due to canister purge valve degradation from vacuum generation due to canister vent valve degradation. A fuel tank vacuum level is monitored after sealing the fuel tank from the atmosphere following an engine pull-down. If there is an ensuing change in fuel tank vacuum, canister purge valve degradation is determined, else, canister vent valve degradation is determined. | 05-15-2014 |
20140209069 | CONTROLLING THE CLOSING FORCE OF A CANISTER PURGE VALVE PRIOR TO EXECUTING LEAK DIAGNOSTIC - A method for a vehicle having a fuel vapor canister coupled between a fuel tank and an engine intake manifold via an electronically controlled purge valve, comprises initiating a vapor leak test under predetermined conditions and in response to said initiation, fully opening said purge valve from a closed position to a fully open position for a predetermined time, and then fully closing said purge valve after said predetermined time and commencing said leak test. | 07-31-2014 |
20140216563 | CAPLESS REFUELING SYSTEM CLEANING USING ENGINE VACUUM - 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. | 08-07-2014 |
20140251284 | MULTI-PATH PURGE EJECTOR SYSTEM - Systems and methods for a multi-path purging ejector are disclosed. In one example approach, a multi-path purge system for an engine comprises an ejector including a restriction, first and second inlets, and an outlet, and a shut-off valve hard-mounted to an intake of the engine and coupled to the outlet. | 09-11-2014 |
20150025722 | LEAK DETECTION BASED ON FUEL LEVEL - Methods and systems for fuel system leak detection are disclosed. In one example approach, a method comprises, during an engine-on condition, delivering fuel from a fuel tank to one or more cylinders of the engine while the fuel tank is sealed off from atmosphere, and indicating a leak based on pressure in the fuel tank. For example, a leak may be indicated in response to a pressure decrease in the fuel tank greater than an expected pressure decrease, where the expected pressure decrease is based on a fuel level in the fuel tank. | 01-22-2015 |
20150046026 | ENGINE-OFF LEAK DETECTION BASED ON PRESSURE - Methods and systems for fuel system leak detection are disclosed. In one example approach, a method comprises, in response to a pressure change in a fuel tank less than a threshold for a duration during engine-off conditions while the tank is sealed off from atmosphere, indicating a leak condition, and in response to a pressure change in the tank greater than the threshold during engine-off conditions while the tank is sealed off from atmosphere, indicating a no-leak condition. | 02-12-2015 |