Methods and systems are provided for generating vacuum via an ejector arranged in a compressor recirculation flow path and an aspirator arranged in a throttle bypass path, where a suction port of the ejector is coupled with a canister purge valve having two outlet ports. In one example, the canister purge valve may include only a single flow restriction, the flow restriction arranged in a path coupling a fuel vapor purge system with the intake manifold when a solenoid of canister purge valve is open, such that a path coupling the fuel vapor purge system with the suction port of the ejector does not include any flow restrictions upstream of the suction port.

An evaporative emissions (EVAP) control system for a vehicle includes a purge pump configured to pump fuel vapor to an engine of the vehicle via a vapor line and a purge valve. The system includes a hydrocarbon (HC) sensor disposed in the vapor line and configured to measure an amount of HC in the fuel vapor pumped by the purge pump to the engine via the vapor line. A controller is configured to: detect an imminent cold start of the engine and, in response to the detecting, perform the cold start of the engine by controlling at least one of the purge pump and the purge valve, based on the measured amount of HC, to deliver a desired amount of fuel vapor to the engine, which decreases HC emissions by the engine.

Methods and systems are provided for controlling a vehicle engine to reduce engine knock and increase fuel efficiency by reducing hydrocarbon breakthrough. In one example, a method may include adjusting a compression ratio of a variable compression engine in response to hydrocarbon breakthrough above a threshold from a fuel vapor canister of an evaporative emissions system.

A fuel tank venting system for a motor vehicle includes an outlet side of a tank venting valve connected to an inlet side of a first vent line and to an inlet side of a second vent line. An outlet side of the first vent line is connected to an intake manifold upstream from a throttle valve and downstream from an air filter, and an outlet side of the second vent line is connected to the intake manifold downstream from the throttle valve. A position sensor may be located at a first position and the first closing element has a detectable element. The position sensor is connected to an electronic control device to transmit signals. A position of the first closing element may be determined by means of the position sensor and the detectable element.

Methods and systems are provided for adjusting and diagnosing one or more canister purge valves in a fuel vapor recovery system. In one example, a method may include adjusting one or more canister purge valves in a passage coupled to a fuel vapor canister of the fuel vapor recovery system to allow flow between an intake passage and an intake manifold of the engine based on engine operating conditions. Further, the method may include indicating the one or more canister purge valves are degraded and based on a change in air-fuel ratio after adjusting the one or more canister purge valves.

A control device of an internal combustion engine including an electronic control unit configured to execute: a base injection amount calculation process of calculating a base value; an injection valve operation process of operating the fuel injection valve; a feedback process of correcting an injection amount in the injection valve operation process; and a determination process of determining whether or not the amount of fuel flowing into the cylinders other than fuel injected from the fuel injection valve is equal to or larger than a threshold value. When it is determined as a result of the determination that the amount of fuel flowing into the cylinders other than the fuel injected from the fuel injection valve is equal to or larger than the threshold value, the electronic control unit (does not execute the process of injecting fuel from the fuel injection valve with the feedback process stopped.

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.

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.

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 engine control device configured to control an engine includes: a turbocharger having a turbine that is configured to be driven by exhaust gas of the engine; and a compressor coupled to the turbine and configured to compress fresh air; an air-bypass passage that communicates between an upstream and a downstream of the compressor; an air-bypass valve configured to open/close the passage; a canister configured to store evaporated fuel gas generated in a fuel tank; an ejector configured to suction the evaporated fuel gas from the canister by using differential pressure between the upstream and the downstream of the compressor and introduce the evaporated fuel gas to the upstream; a purge valve configured to open/close a purge passage through which the evaporated fuel gas is to delivered from the canister to the ejector; and a purge valve diagnosis unit configured to detect stuck open malfunction of the purge valve.