In a vaporized fuel processing apparatus in which fuel vapor within a fuel tank is adsorbed by a canister, the adsorbed vaporized fuel is drawn to an engine, a closing valve is provided connecting the fuel tank and the canister for controlling communication between the fuel tank and the canister, and a purge valve is provided connecting the canister and the engine for controlling communication between the canister and the engine. The vaporized fuel processing apparatus includes an internal pressure sensor configured to detect a pressure of a space within the fuel tank as an internal pressure, and a closing valve control means configured to open the closing valve for supplying an atmospheric pressure to the fuel tank via the canister when the sensor detects that the internal pressure of the fuel tank is negative, while the purge valve is closed. Therefore, the air/fuel ratio is prevented from being disturbed.

An evaporative emissions control system for an internal combustion engine having an air intake manifold is provided. The system includes a carbon canister configured to receive fuel vapor, a purge valve fluidly coupled to the carbon canister, an air induction system configured to fluidly couple to the air intake manifold, a conduit fluidly coupled between the purge valve and the air induction system, and an inlet valve disposed in the air induction system. The inlet valve is configured to selectively move between an open position and a closed position to vary an air restriction in the air induction system and generate a vacuum. The vacuum draws fuel vapor from the carbon canister through the conduit into the air induction system.

A vaporized-fuel treating apparatus includes a pump part for controlling a flow of purge gas and a heating part for controlling driving of the pump part and for generating heat. At least a part of the heating part is placed to be exposed in an atmosphere passage. The pump part is either placed in the purge passage or arranged connecting to the purge passage.

A purge system of a vehicle for purging CH-gas of a tank system to an induction line of a combustion engine of the vehicle. The purge system includes a purge unit, a control unit for operating the purge unit and gas connection lines, wherein a first line end of the gas connection lines is configured for connecting the purge unit with the tank system and a second line end of the gas connection lines is configured for connecting the purge unit with the induction line. The purge system also includes a CH-sensor for measuring a CH-gas concentration of a fluid volume flow that flows from the first line end towards the second line end. A vehicle and a method for operating a combustion engine system of a vehicle with a purge system is also provided.

Various methods and systems are provided for correcting relative error between a gaseous fuel torque estimate and a liquid fuel torque estimate in a multi-fuel engine. A system (e.g., a system for an engine) may include a controller with computer readable instructions stored on non-transitory memory that when executed during operation of the engine cause the controller to: operate the engine at a first substitution ratio of gaseous fuel and liquid fuel; correct for relative error between a gaseous fuel to torque conversion factor and a liquid fuel to torque conversion factor; and upon correcting for the relative error, operate the engine at a second substitution ratio, higher than the first substitution ratio.

Both an improvement in detection accuracy of a valve opening position of a blocking valve and a reduction in time required for learning of the valve opening position are achieved. An evaporated fuel processing apparatus is provided with a learning device configured to learn the valve opening position of the blocking valve. The learning device learns the valve opening position (i) by stepwisely increasing a stroke amount by rotating a stepping motor by two steps at each time in a valve opening direction and (ii) by determining whether a difference between the stroke amount at present and the stroke amount corresponding to the valve opening position is one step of rotation of the stepping motor, or two steps, on the basis of pressure fluctuation on the canister side of the blocking valve associated with the rotation of the stepping motor when the blocking valve is opened, when learning the valve opening position.

A vehicle fuel system includes a turbocharger having a compressor disposed on an intake line of an engine. The compressor selectively compresses intake air supplied to the engine. The fuel system has a canister configured to capture fuel vapor discharged from a fuel tank and a purge control valve configured to open or close the purge line depending on a pressure of the intake line. The fuel system has a check valve provided on the purge line that blocks movement of a fluid from the intake line to the canister. The fuel system has a controller performing control such that the purge control valve is operated in a closed mode to prevent intake air in the intake line from being introduced into the fuel tank when breakdown of the check valve is sensed during driving of the vehicle.

An evaporated fuel treatment device is provided in a canister including first to third chambers. The first chamber is provided with an inflow port and an outflow port at an end part thereof, and is connected to the second chamber. The evaporated fuel treatment device is configured as the third chamber of the canister. The third chamber has disposed therein activated carbon as an adsorbent material. The side connected to the second chamber in the third chamber is defined as second chamber side, and the side opposite to the second chamber side is defined as atmosphere side. An atmosphere port is provided at an end part on the atmosphere side of the third chamber. The third chamber is provided with a highly adsorptive layer and a low adsorptive layer which are aligned from the second chamber side to the atmosphere side.

An evaporative fuel treatment apparatus includes a canister, a vapor passage, an outside air introduction passage, a purge passage that connects the canister and an intake passage to each other, a sealing valve configured to open/close a flow channel of the vapor passage, a tank internal pressure sensor, a pressure sensor configured to detect a vapor pressure; and an electronic control unit. The electronic control unit is configured to determine whether or not there is an abnormality in the tank internal pressure sensor based on a change in the vapor pressure in changing over the sealing valve from a closed state to an open state, when an amount of change in the tank pressure in changing over the sealing valve from the closed state to the open state is lower than a first predetermined value.

Methods and systems are provided for conducting vehicle fuel system and/or evaporative emissions system diagnostics, where the diagnostics rely on a positive pressure with respect to atmospheric pressure. In one example, a method comprises activating an electric compressor positioned in an intake of an engine configured to receive purge gasses from the evaporative emissions system under boosted engine operation and natural engine operation, to direct a positive pressure with respect to atmospheric pressure to the fuel system and/or evaporative emission system to conduct said diagnostic. In this way, diagnostics that rely on positive pressure with respect to atmospheric pressure may be conducted in vehicles with a dual-path purge system, without introduction of a pump in the evaporative emissions system.