A method for operating an internal combustion engine having a cylinder, an intake valve, an air pipe, and a valve element disposed in the air pipe, includes detecting a signal for causing a fuel supply of the cylinder to switch off. The valve element is moved out of a first position into a second position triggering a lower flow cross-section while the fuel supply is still activated, where a first cam for actuating the intake valve is allocated to the intake valve. While the fuel supply is still activated, switching from the first cam to a second cam and via the second cam the intake valve is actuated such that the intake valve causes a reduced air intake. An exhaust cam shaft for actuating an exhaust valve is set in an advance direction such that a valve intersection of the intake valve and of the exhaust valve ceases.

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.

Methods and systems are provided for improving fuel vapor storage canister purging operations for vehicles with dual-path purge systems. In one example, a method may include purging fuel vapors from a fuel vapor storage canister to an engine of a vehicle via a single path, and in response to an unmetered increase in a concentration of the fuel vapors being purged to the engine via the single path, switching the fuel vapors to be purged to the engine via two paths simultaneously. In this way, fuel vapors may be distributed in time along the two paths, which may lower an effective concentration of fuel vapors entering the engine and may thereby avoid degradation of engine operating conditions.

An internal combustion engine is provided with: an electric supercharger including an electric compressor; an EGR introduction port formed upstream of the electric compressor; a throttle valve A arranged upstream of the EGR introduction port; and a control device. A throttle valve B other than the throttle valve A is not arranged in the intake air passage. The control device is configured, in a non-supercharging region, to execute a first air flow rate adjustment processing that adjusts an intake air flow rate by adjusting the opening degree of the throttle valve A while driving the electric supercharger to cause a pressure ratio of the electric compressor to approach 1; and a second air flow rate adjustment processing that adjusts the intake air flow rate by adjusting the opening degree of the throttle valve A while not energizing the electric supercharger.

A method of securing brake booster negative pressure is provided. The method includes operating a purge pump that is connected to a canister having evaporation gas absorbed thereon and a brake booster and determining whether the evaporation gas is injected into an intake pipe by the operation of the purge pump. Whether a negative pressure of the brake booster is insufficient is determined and when the evaporation gas is being injected into the intake pipe and the negative pressure is insufficient, a degree of opening of a valve provided in a line connecting the canister and the purge pump is adjusted.

A hybrid vehicle includes an engine, a first MG, a second MG, a planetary gear mechanism, and an HV-ECU. The engine includes a supercharger and a purge device. The purge device introduces fuel vapor into an intake passage of the engine. Upon request for fuel purge, when an operating point of the engine is included in an area A, the HV-ECU controls the engine and the first MG to move the operating point to outside of the area A.

A system for controlling a compressor may include an engine controller that controls a fuel injection amount corresponding to an engine load and an opening amount of a throttle by reflecting a required torque required for an air conditioner (A/C), an operation information detector for detecting operation information according to driving state of the vehicle, a compressor that generates pressure during operation of the A/C, an air conditioner relay which is turned on when the air conditioner operates and is turned off when the A/C is stopped, and a controller which determines an engine negative pressure of an intake manifold, and when the cooling water temperature is lower than the predetermined temperature and the intake manifold pressure is lower than the first threshold value, a cold-start intake manifold negative pressure insufficient event is generated to reduce the A/C duty in accordance with the entry into a negative pressure recovery mode.

An intake control method for an internal combustion engine equipped with a low-pressure EGR system includes setting a target intake pressure, which is a target value of an intake pressure in an intake passage between a negative pressure generating valve and an intake throttle valve, necessary for performing EGR control in a state of an exhaust pressure determined for each operating point, setting a target total opening area, which is a sum of a target opening area of an EGR valve and a target opening area of the negative pressure generating valve, on the basis of the target intake pressure, a target fresh air amount, and a target EGR gas amount, setting a target EGR valve opening area, which is an opening area of the EGR valve for achieving the target EGR gas amount, assuming that the negative pressure generating valve is fully open, and setting a value obtained by subtracting the target EGR valve opening area from the target total opening area to be a target negative pressure generating valve opening area, which is a target value of an opening area of the negative pressure generating valve.

When atmospheric pressure (Pa) which varies according to altitude is higher than a predetermined pressure threshold (Path) during idle operation in which catalyst warm-up request is issued, an intake pressure is controlled, through a throttle valve (19), to an intake pressure at which an intake air amount required to promote the warm-up of a catalyst converter (26) is obtained. When the atmospheric pressure (Pa) is lower than the predetermined pressure threshold (Path), the intake pressure is controlled, through a throttle valve (19), to an intake pressure (PaPb) at which a differential pressure (Pb) required by a brake booster (8) is obtained. Accordingly, negative pressure in the brake booster (8) can be secured while promoting the warm-up of the catalyst during the idle operation.

Methods and systems are provided for improving fuel vapor storage canister purging operations for vehicles with dual-path purge systems. In one example, a method may include purging fuel vapors from a fuel vapor storage canister to an engine of a vehicle via a single path, and in response to an unmetered increase in a concentration of the fuel vapors being purged to the engine via the single path, switching the fuel vapors to be purged to the engine via two paths simultaneously. In this way, fuel vapors may be distributed in time along the two paths, which may lower an effective concentration of fuel vapors entering the engine and may thereby avoid degradation of engine operating conditions.