Systems and methods for diagnosing ejector system degradation for dual-path purge engine systems
AssigneeFord Global Technologies, LLC
InventorAed Dudar
Life of this patent
Estimating the term…
Abstract
Methods and systems are provided for conducting an ejector system diagnostic under conditions where an engine of a vehicle is not combusting air and fuel. In one example, a method comprises directing a positive pressure to the ejector system while the engine is off in order to communicate a negative pressure with respect to atmospheric pressure on a fuel system and an evaporative emissions system of the vehicle, and indicating that the ejector system is degraded responsive to the negative pressure not reaching a vacuum build threshold. In this way, the ejector system may be diagnosed under conditions where boosted engine operation is infrequent and/or of durations insufficient for conducting such an ejector system diagnostic.
Claims20
A method comprising:
- while an engine of a vehicle is off and a set of predetermined conditions are met, directing a positive pressure with respect to atmospheric pressure into an ejector system to communicate a negative pressure with respect to atmospheric pressure on a fuel system and an evaporative emissions system;
- and
- indicating that the ejector system is degraded in response to the negative pressure not reaching a vacuum build threshold.
A method comprising:
- during a condition where an engine of a vehicle is not combusting air and fuel, selectively fluidically coupling a pump positioned in a vent line stemming from a fuel vapor storage canister to an ejector system;
- routing a positive pressure with respect to atmospheric pressure into the ejector system via the pump in order to reduce a pressure in a fuel system and an evaporative emissions system of the vehicle;
- and
- indicating that the ejector system is not degraded responsive to the pressure in the fuel system and the evaporative emissions system being reduced to a vacuum build threshold.
A system for a vehicle, comprising:
- a pump that is selectively fluidically coupled to a vent line upstream of a fuel vapor storage canister positioned in an evaporative emissions system when a routing valve is commanded to a first routing valve position, and that is alternatively selectively fluidically coupled to an ejector system when the routing valve is commanded to a second routing valve position;
- and
- a controller with computer readable instructions stored on non-transitory memory that when executed during an engine-off condition, cause the controller to:
- command the routing valve to the second position, activate the pump to route a positive pressure to the ejector system;
- monitor a vacuum generated via the ejector system responsive to routing the positive pressure to the ejector system;
- and
- indicate that the ejector system is degraded responsive to the vacuum failing to reach or exceed a vacuum build threshold.
Dependencies are inferred from the claim text.