Methods and systems are provided herein for increasing an efficiency of an evaporative emissions system of a vehicle by adjusting a purge flow in response to a predicted vapor slug. In one example, a method for an engine of a vehicle includes, upon approaching a location of a predicted vapor slug, ramping down a purge flow rate from a fuel vapor canister to an engine intake, the location of the predicted vapor slug inferred based on communication of the vehicle with one or more other vehicles and/or a network cloud.

Systems and methods for estimating a temperature of an after treatment device in an exhaust system of an engine are described. In one example, the temperature is estimated during condition when an engine is in a fuel cut-out mode and fuel vapors are being released to the engine via a fuel vapor storage canister.

A first arrival flow rate that is a flow rate of evaporative fuel gas that has arrived in a throttle downstream portion located downstream of a throttle valve in an intake pipe via a second purge passage after passing through a purge control valve is estimated based on a valve passage flow rate that is a flow rate of evaporative fuel gas that has passed through the purge control valve, and a first response delay in the flow of evaporative fuel gas through a route extending from the purge control valve to the throttle downstream portion via the second purge passage.

When a predetermined condition is satisfied, a flow rate ratio of a first passage flow rate to a second passage flow rate is estimated based on a throttle post pressure being a pressure on a downstream side of an intake pipe with respect to a throttle valve and an ejector pressure being a pressure of a suction port of an ejector. The first passage flow rate is a flow rate of an evaporated fuel gas flowing in a first purge passage. The second passage flow rate is a flow rate of the evaporated fuel gas flowing in a second purge passage. The first passage flow rate and the second passage flow rate are estimated based on the flow rate ratio and a valve passing flow rate being a flow rate of the evaporated fuel gas that passes through a purge control value.

An evaporated fuel treatment apparatus is provided with a purge pump and a purge valve and an electronic control unit (ECU) for controlling the purge pump and the purge valve. The ECU, when performing purging, opens the purge valve to control the purge pump at the rated rotational speed, and when stopping purging, closes the purge valve to control the purge pump at a zero rotational speed. When starting purging, the ECU gradually controls the purge pump from a rotational speed lower than the rated rotational speed toward the rated rotational speed before opening the purge valve which is in the closed state, and opens the purge valve when the purge pump reaches a first threshold rotational speed lower than the rated rotational speed during the performing the control.

An evaporated fuel processing device is installed to a vehicle having an internal combustion engine and a fuel tank and is configured to process evaporated fuel generated through evaporation of fuel in the fuel tank. A control device of the evaporated fuel processing device is configured to adjust an opening degree of a sealing valve based on a pressure of vapor-phase gas sensed with a pressure sensor and a concentration of evaporated fuel in the vapor-phase gas sensed with a concentration sensor and thereby adjust a supply amount of the evaporated fuel supplied to an air intake pipe at a time of executing a purge operation, in which the vapor-phase gas is purged from the fuel tank to the air intake pipe of the internal combustion engine.

An evaporated fuel processing device includes a canister; a purge passage connecting the canister and an intake pipe of an engine; a purge control valve on the purge passage; and a controller that controls switching timings for the purge control valve and a fuel injection valve that supplies fuel to the engine. The controller estimates whether a catalyst temperature would exceed a criteria temperature if the purge gas is supplied to the engine while the engine is in operation and a fuel supply from the fuel tank to the engine is stopped, and in a case where the catalyst temperature is estimated to exceed the criteria temperature, the controller reduces the purge gas amount before the fuel supply to the engine is stopped such that the catalyst temperature becomes equal to or lower than the criteria temperature when the fuel supply to the engine is stopped.

The present disclosure relates to an active purge system and an active purge method for a hybrid vehicle, and changes a control method for the throughput of the evaporation gas according to the engine torque according to a change in an optimal operating line, the system efficiency, or the state of charge (SOC) condition of a battery using an active purge unit for pressing the evaporation gas generated by a fuel tank and supplying the pressed evaporation gas to an intake pipe, thereby efficiently purging the evaporation gas.

A method for determining the load of a fuel vapor retention filter in a fuel evaporation retention system of an internal combustion engine. The fuel evaporation retention system includes: a fuel supply container for storing fuel, a connection line which couples the fuel supply container to the fuel vapor retention filter, a regeneration line which couples the fuel vapor retention filter to an intake tract of the internal combustion engine and in which an electrically controllable flow control valve is arranged, a ventilation line which couples the fuel vapor retention filter to the atmosphere, an electrically controllable purging air pump arranged in the regeneration line, such that purging air can be directed through the fuel vapor retention filter and supplied to the intake tract in order to regenerate the fuel vapor retention filter.

A purge control unit opens the purge control valve to supply, as purge gas to an intake passage, the evaporative fuel together with air in response to a predetermined purge request. An air-fuel ratio detection unit detects an air-fuel ratio of the internal combustion engine. A concentration learning unit estimates a fuel concentration in the purge gas based on a change in the air-fuel ratio when the purge control unit causes the purge gas to be supplied to the intake passage and to perform a fuel concentration learning to update a concentration learning value, which is a learning value of the fuel concentration in the purge gas, based on the estimated fuel concentration. An injection control unit corrects a fuel injection amount based on the concentration learning value in a period in which the concentration learning unit performs the fuel concentration learning in the lean combustion operation.