Embodiments for controlling fuel vapors are disclosed. In one example, a method comprises during a purge of a fuel vapor canister, adjusting a heater of the fuel vapor canister based on a rate of a purge flow exiting the fuel vapor canister and a concentration of hydrocarbons released from the fuel vapor canister. In this way, a fuel vapor canister purge efficiency may be increased.

Methods and systems are provided for controlling canister purge flow in a boosted engine. An example method for the boosted engine comprises, during boosted conditions, flowing stored fuel vapors from a canister into an ejector coupled in a compressor bypass passage, the flowing bypassing a canister purge valve. The method further comprises, responsive to a canister load higher than a threshold load, closing a canister vent valve coupled to the canister, and discontinuing flowing stored fuel vapors from the canister into the ejector.

A controller for an internal combustion engine is provided. The engine includes a compressor, a three way catalyst, a canister, an evaporated fuel passage, an ejector, and a purge control valve. The controller includes an ECU. The ECU is configured to decrease an opening degree of the purge control valve in response to an increase in pressure on the downstream side of the compressor in a lean supercharging range. The is a range in which an operation air-fuel ratio of the internal combustion engine is leaner than a theoretical air-fuel ratio of the internal combustion engine, and in which the pressure on the downstream side of the compressor is higher than pressure on the upstream side of the compressor.

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.

A method is presented, comprising, during a first condition, including an active refueling event, receiving an indication of hydrocarbon breakthrough from the fuel vapor canister; and restricting flow of fuel vapor through a fuel vapor canister vent pathway responsive to the indication of hydrocarbon breakthrough. Restricting the fuel vapor canister vent pathway will cause fuel tank pressure to increase, thus triggering an automatic shutoff of a refueling dispenser. In this way, the refueling event may be terminated without releasing significant quantities of hydrocarbons into the atmosphere.

A vaporized-fuel treating apparatus is configured to perform purge control in which a purge valve is placed in an open state while a purge pump is being driven to introduce purge gas from a canister to an intake passage through a purge passage. When an actual value of a flow rate of the purge gas during execution of the purge control is defined as an actual purge flow rate, and an upper-limit value of the purge flow rate to prevent the occurrence of A/F disturbance where A/F in a combustion chamber of an engine excessively fluctuates, as an upper-limit purge flow rate, the number of rotations of the purge pump is controlled during execution of the purge control to adjust the actual purge flow rate to a value equal to or lower than the upper-limit purge flow rate.

An engine apparatus includes an engine, a supercharger, an evaporated fuel treatment device, a controller and the engine apparatus is configured to determine a purge classification whether the evaporated fuel is a first purge in which the evaporated fuel flows dominantly in a first purge passage or a second purge in which the evaporated fuel flows dominantly in a second purge passage based on a relative ejector pressure that is a pressure of a suction port of the ejector and a value obtained by adding an offset amount based on a cross-sectional area of the second purge passage with respect to a cross-sectional area of the first purge passage to a pressure behind a throttle valve that is the pressure on a downstream side of the throttle valve of the intake pipe.

Methods and systems are provided for controlling the purging of a fuel vapor canister coupled to a vehicle fuel tank, configured for capturing and storing vapors emanating from the tank. In one example, two canister purge valves are coupled in series in a fuel vapor conduit between the fuel vapor canister and engine intake, one at the intake manifold and one at the fuel vapor canister, such that fine control over the introduction of fuel vapors into the engine is maintained via the purge valve at the intake manifold, while thorough purging of the fuel vapor canister may be regulated via the purge valve at the fuel vapor canister. In this way, fuel vapors in the fuel vapor canister may be effectively purged to intake, thus reducing the potential for undesired evaporative emissions.

The disclosure relates to a method for ascertaining the flow through a timer valve. The method includes detecting the pressure upstream of the timer valve during an evacuation of a container arranged upstream of the timer valve, ascertaining the flow through the timer valve based on the detected pressure upstream of the timer valve and based on the temperature and the volume of the gas in the container. The method also includes comparing the flow ascertained during the evacuation and a modeled flow and/or comparing a variable dependent on the ascertained flow and a variable dependent on the modeled flow. Additionally, the method includes adapting the model in the event of a discrepancy between the flow ascertained during the evacuation and the modeled flow and/or in the event of a discrepancy between the variable dependent on the ascertained flow and the variable dependent on the modeled flow.

A method for venting the tank of a vehicle, a device for venting the tank of a vehicle, as well as a vehicle are provided. In this context, the vehicle in which the method is employed has an internal combustion engine that can be operated with a fuel, an air supply system, an exhaust gas system comprising at least an exhaust gas turbocharger, a fuel tank that is designed to supply the internal combustion engine with fuel, and a fuel vapor sorption system. It is provided that, in the method or by means of the device, a drive flow in the air supply system is regulated as a function of an altitude reserve of the exhaust gas turbocharger and as a function of an engine load point, so that the flushing air volume flow of the tank venting system that ensues is determined and can be supplied as a function of an altitude rotational speed of the exhaust gas turbocharger and as a function of the engine load point.