Patent application number | Description | Published |
20140026992 | FUEL TANK DEPRESSURIZATION WITH SHORTENED WAIT TIME - A method and apparatus for a pressurized fuel system with a fuel tank, a fuel fill pipe, and a remotely-controlled lockable fuel opening which selectably seals the pipe entrance. A carbon canister has an inlet for receiving a flow of air and fuel vapors from the tank and has an outlet providing a treated air flow to atmosphere. A fuel tank isolation valve is connected between the air space and the inlet of the carbon canister for selectively allowing pressurization of the fuel tank, wherein the pressurization must be relieved prior to refilling of fuel to the fuel tank. A vacuum pump is coupled to the outlet of the carbon canister, wherein the vacuum pump is configured to activate to increase air flow through the carbon canister from the fuel tank when the fuel tank isolation valve is opened during refilling. | 01-30-2014 |
20140096749 | MULTI-TUBULAR FUEL VAPOR CANISTER - Systems and methods for operating an engine with a fuel vapor recovery system are disclosed. In one example approach, a method for an engine with a fuel vapor recovery system including a multi-tubular fuel vapor canister comprises directing air through a first set of adsorbent passages in the fuel vapor canister to purge fuel vapor therefrom while not directing air through a second set of adsorbent passages in the fuel vapor canister; and directing air through the second set of adsorbent passages to purge fuel vapor therefrom while not directing air through the first set of adsorbent passages. | 04-10-2014 |
20140311461 | CANISTER PURGE VALVE SELF-CLEANING CYCLE - A method for a fuel system coupled to an engine comprising: under vacuum conditions, opening the fuel vapor canister purge valve, and generating pressure pulsations in a conduit coupled to the fuel vapor canister purge valve by opening and closing a fuel vapor canister vent valve one or more times while maintaining the fuel vapor canister purge valve open. In this way, contaminants and/or debris that may prevent the canister purge valve from closing completely may be dislodged and evacuated to the intake manifold. | 10-23-2014 |
20140316638 | HYBRID VEHICLE FUEL SYSTEM LEAK DETECTION - Methods and systems for fuel system leak detection in a hybrid electric vehicle using a fuel reservoir are disclosed. In one example approach, a method comprises, during an engine off condition, delivering fuel from a fuel tank into a reservoir while the fuel tank is vented to atmosphere, and sealing the fuel tank from atmosphere and indicating a leak based on pressure in the fuel tank. | 10-23-2014 |
20140318504 | AIR INTAKE SYSTEM HYDROCARBON TRAP PURGING - Methods and systems for purging a hydrocarbon trap in an engine intake in a vehicle are disclosed. In one example approach, a method comprises during an engine off condition, operating a pump in a purge line coupled to a fuel vapor canister in an emission control system to deliver fuel stored in a hydrocarbon trap in an intake of the engine to the fuel vapor canister. | 10-30-2014 |
20140318506 | AIR INTAKE SYSTEM HYDROCARBON TRAP PURGING - Methods and systems for passively purging a hydrocarbon trap in an engine intake in a vehicle are disclosed. In one example approach, a method comprises, in response to an ambient temperature decrease during an engine off condition while a fuel tank is sealed from atmosphere, delivering fuel stored in a hydrocarbon trap in an intake of the engine to a fuel vapor canister coupled to the fuel tank in an emission control system. | 10-30-2014 |
20140330482 | REFUELING DETECTION FOR DIAGNOSTIC MONITOR - Methods and systems for detecting a refueling event for diagnostics are disclosed. In one example approach a method comprises discontinuing leak diagnostics in response to a temperature change in a fuel vapor canister coupled to a fuel tank in an emission control system while the leak diagnostics are being performed in the emission control system. | 11-06-2014 |
20140336873 | INTERNAL ORIFICE CHARACTERIZATION IN LEAK CHECK MODULE - Systems and methods for internal orifice characterization in an evaporative leak check module are disclosed. In one example approach, a method comprises operating a pump to draw air from an emission control system through an orifice to obtain a reference pressure, and indicating a leak in response to pressure in the emission control system remaining above a threshold pressure while operating the pump to decrease pressure in the emission control system, where the threshold pressure is based on a coded indication and the reference pressure. | 11-13-2014 |
20140345575 | CANISTER PURGING FOR PLUG-IN HYDRID ELECTRIC VEHICLES - A method for desorbing fuel vapors from a canister of a vehicle having an internal combustion engine and a fuel tank includes detecting the temperature within the interior of the fuel tank using a temperature sensor positioned within the fuel tank. The canister is in fluid communication with the fuel tank and an intake manifold of the engine of the vehicle. A vapor bypass valve is positioned along a flow line between the fuel tank and the canister. The vapor bypass valve is opened if the temperature inside the fuel tank falls below a pre-determined value. The low pressure region created within the fuel tank due to fall in temperature is utilized to route ambient air along with the fuel-vapors contained within the canister, towards the fuel tank, through the opened vapor bypass valve. | 11-27-2014 |
20140352796 | FUEL TANK DEPRESSURIZATION BEFORE REFUELING A PLUG-IN HYBRID VEHICLE - Methods and systems for controlling a locking mechanism on a fuel cap for refueling a vehicle are disclosed. In one example approach, a method comprises venting a fuel tank into a vapor absorbent canister in response to a request to refuel and unlocking the fuel cap in response to a predetermined temperature change in said canister. | 12-04-2014 |
20140360260 | FUEL LEVEL INFERENCE FROM CANISTER TEMPERATURES - Methods and systems for inferring a fuel level in a fuel tank based on temperature changes in a carbon canister are disclosed. In one example approach a method comprises, indicating a fuel level in a fuel tank based on a temperature change of adsorbent in a carbon canister during refueling. | 12-11-2014 |
20140374177 | FUEL SYSTEM CONTROL - Methods and systems are provided for accurately confirming fuel tank depressurization before unlocking a fuel door to enable refueling. Following a refueling request, a fuel system may be sealed from the atmosphere while one or more fuel system valves are adjusted to divert fuel tank pressure or vacuum to an engine intake. Depressurization may be inferred based on the presence of air or vapor flow into the intake as sensed by a manifold airflow sensor. | 12-25-2014 |
20150019066 | LEAK DETECTION FOR CANISTER PURGE VALVE - Methods and systems for detecting a leak in a canister purge valve are disclosed. In one example approach, a method comprises indicating a leak in response to a temperature change in a fuel vapor canister coupled to a fuel tank in an emission control system while the engine is in operation and a purge valve is closed. | 01-15-2015 |
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 |
20150025781 | CANISTER PURGE VALVE LEAK DETECTION SYSTEM - System for detecting leakage within a canister purge valve of an evaporative emission control system. The system includes a power train control module connected to the canister purge valve, configured to command the canister purge valve between open and closed positions. In addition, the system includes a flow meter having an inlet and an outlet. The inlet is in fluid communication with ambient air surrounding the vehicle, and the outlet is in fluid communication with an inlet of the canister purge valve. The system further includes a control module operatively connected to the flow meter. The control module is programmed to analyze flow through the flow meter; compare the measured flow to predetermined flow data; and to indicate whether that flow exceeds a predetermined level. | 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 |
20150068498 | SYSTEMS AND METHODS FOR A TWO-VALVE NON-INTEGRATED REFUELING CANISTER ONLY SYSTEM - 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. | 03-12-2015 |
20150083087 | METHOD AND SYSTEM FOR FUEL VAPOR CONTROL - 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. | 03-26-2015 |
20150083088 | METHOD AND SYSTEM FOR DETECTING PHEV EVAP SYSTEM RECIRCULATION TUBE RELIABILITY - 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. | 03-26-2015 |
20150085894 | METHOD FOR DIAGNOSING FAULT WITHIN A FUEL VAPOR SYSTEM - A method for diagnosing a fault within a evaporative emission control system of an automotive vehicle. The method monitors the carbon canister temperature during a system leak test. The leak test here is undertaken with the engine running, and engine vacuum is employed to evacuate the EVAP system. If the evacuation succeeds in reaching a target vacuum, and a temperature gain in the canister is observed, then the system infers proper system operation. Failure to achieve a target vacuum causes the system to determine a likely cause of the failure based on the temperature response of the carbon canister. | 03-26-2015 |