Systems and methods for vehicle multi-canister evaporative emissions systems
AssigneeFord Global Technologies, LLC
InventorAed M. Dudar
Life of this patent
Estimating the term…
Abstract
Methods and systems are provided for pinpointing a restriction in a vehicle evaporative emissions system which may adversely impact refueling and/or fuel vapor canister purging operations. In one example a method comprises conducting a diagnostic to identify a location of a restriction based on a rise time at which a pressure in a fuel system of a vehicle rises to a threshold pressure during a refueling event where fuel is added to the fuel system. In this way, a location of the restriction may be identified so as to enable appropriate mitigating action to be taken.
Claims20
A method comprising:
- diagnosing an evaporative emissions system including identifying a location of degradation in an evaporative emissions system of a vehicle based on a rise time at which a pressure in a fuel system of the vehicle rises to a threshold pressure during a refueling event where fuel is added to the fuel system via a refueling dispenser.
A method comprising:
- conducting an evaporative emissions system diagnostic to identify a location of a restriction in an evaporative emissions system of a vehicle based on a pressure rise time between a first time at which fuel is commenced being added to a fuel system of the vehicle via a refueling dispenser and a second time corresponding to a premature shutoff of the refueling dispenser;
- and
- controlling a valve positioned in the evaporative emissions system in response to the identified location of the restriction.
A system for a vehicle, comprising:
- an evaporative emissions system fluidically coupled to a fuel system that includes a fuel tank, the evaporative emissions system including two or more fuel vapor storage canisters;
- a fuel tank pressure transducer and a fuel level indicator coupled to the fuel tank;
- and
- a controller with computer readable instructions stored on non-transitory memory that when executed during a refueling event of the fuel system, cause the controller to:
- monitor a rise time of a pressure via the fuel tank pressure transducer between a first time point when a fuel level in the fuel tank begins rising and a second time point when the fuel level in the fuel tank prematurely stops rising prior to the fuel level reaching a capacity of the fuel tank, the fuel level monitored via the fuel level indicator;
- compare the rise time to a set of baseline rise times;
- indicate a location of a restriction in the evaporative emissions system based on comparing the rise time to the set of baseline rise times;
- and
- responsive to the location of the restriction comprising a fuel vapor storage canister, route a fluid flow around the fuel vapor storage canister.
Dependencies are inferred from the claim text.