A vehicle control system includes a processor programmed to control a vehicle subsystem according to a recovered signal generated from an output signal of a sensor, and a product of a time constant of the sensor and filtered changes of the output signal with respect to time such that a magnitude and phase of the recovered signal approach a magnitude and phase of an input signal to the sensor.

A port injection valve injects fuel to an intake passage. In multiple injection processing, a demanded injection quantity of the fuel is divided into a synchronous injection quantity and a non-synchronous injection quantity in accordance with at least one of: the load, which is a physical quantity having a correlation with the amount of air to be filled; and the temperature of an internal-combustion engine. The fuel is injected through intake non-synchronous injection and intake synchronous injection in this order. In the intake synchronous injection, the fuel is injected synchronously with a valve-open period of an intake valve. In the intake non-synchronous injection, the fuel is injected at a timing more advanced than in the intake synchronous injection.

A method for diagnosing leakage of a fuel vapor dual purge system is provided. The method includes determining whether an operation region of a vehicle is an operation region in which a turbocharger is operated and adjusting a flow amount of intake air flowing into the turbocharger according to an operation region in which the turbocharger is operated. A hydrocarbon collecting amount of a canister connecting fuel vapor generated in the fuel tank is calculated and a flow amount of the fuel vapor passing first and second purge lines is adjusted. A leak of the fuel vapor is diagnosed in the first purge line and the second purge line.

An air amount control valve of a vehicle changes an intake air amount drawn into a cylinder. A fuel cutoff process stops fuel injection from a fuel injection valve when stopping combustion in the cylinder in a case in which a crankshaft is rotating. When execution of the fuel cutoff process is requested, a temperature-increase limiting process is executed to draw fresh air into a catalyst by increasing the intake air amount through control of the air amount control valve. In a case in which an anomaly occurs in driving of the air amount control valve when executing the temperature-increase limiting process, an amount of air drawn into the catalyst is increased by increasing an engine speed.

A physical quantity measurement device includes a measurement channel through which the fluid flows to be measured, a physical quantity detector that detects a physical quantity of a fluid in the measurement channel, a housing forming the measurement channel, and a measurement outlet provided in the housing as a downstream end of the measurement channel. An outer peripheral surface of the housing includes an outer peripheral flat surface that extends in an arrangement direction along which an upstream end and a downstream end of the housing are arranged, and an outer peripheral inclined surface inclined with respect to the outer peripheral flat surface and provided between the upstream end and the outer peripheral flat surface in the arrangement direction. The measurement outlet is positioned upstream of the downstream end of the housing.

An air amount control valve of a vehicle changes an intake air amount drawn into a cylinder. A fuel cutoff process stops fuel injection from a fuel injection valve when stopping combustion in the cylinder in a case in which a crankshaft is rotating. When execution of the fuel cutoff process is requested, a temperature-increase limiting process is executed to draw fresh air into a catalyst by increasing the intake air amount through control of the air amount control valve. In a case in which an anomaly occurs in driving of the air amount control valve when executing the temperature-increase limiting process, an amount of air drawn into the catalyst is increased by increasing an engine speed.

An internal combustion engine comprises an exhaust purification catalyst, a downstream side air-fuel ratio sensor which is arranged at a downstream side of the exhaust purification catalyst, and an air flow meter which detects an amount of intake air. The control system of the internal combustion engine controls the exhaust air-fuel ratio to a target air-fuel ratio by feedback control, sets the target air-fuel ratio at a lean air-fuel ratio when the output air-fuel ratio of the downstream side air-fuel ratio sensor becomes a rich air-fuel ratio, and sets the target air-fuel ratio at a rich air-fuel ratio when the output air-fuel ratio of the downstream side air-fuel ratio sensor becomes a lean air-fuel ratio. When a change in the amount of intake air occurs so that it increases, the lean degree is set lower than before, in at least part of the time period during which the target air-fuel ratio is set to the lean air-fuel ratio, and the rich degree is set lower than before, in at least part of the timer period during which the target air-fuel ratio is set to the rich air-fuel ratio.

A control system for an engine includes one or more processors configured to determine when a change in one or more of oxygen or fuel supplied to an engine. The one or more processors also are configured to, responsive to determining the change in oxygen and/or fuel supplied to an engine, direct one or more fuel injectors of the engine to begin injecting fuel into one or more cylinders of the engine during both a first fuel injection and a second fuel injection during each cycle of a multi-stroke engine cycle of the one or more cylinders.

In order to adequately suppress both an increase in NOx emission amount and deterioration of fuel consumption rate, the present invention provides a fuel injection control information generation device equipped with: a test point information storage unit for holding test point information including a plurality of test points constituted by sets of engine speed, fuel injection amount, and oxygen concentration; and a control information generation unit for generating, for each test point included in the test point information, fuel injection control information in which the engine speed, fuel injection amount, and oxygen concentration of the test point are associated with an optimum fuel injection timing at which an index pertaining to the total of a fuel consumption rate and an NOx emission amount in the test point becomes the smallest.

The control apparatus for an engine includes: a first controller that sets a valve-opening timing of an intake valve of the engine in response to an amount of intake air; and a second controller that sets an injection start time of a fuel injector of the engine in response to the amount of intake air. In a case where the amount of intake air is within a first range being equal to or more than a predetermined value, the first controller advances the valve-opening timing as compared with a case where the amount of intake air is equal to the predetermined value, and the second controller delays the injection start time as compared with a case where the amount of intake air is within a second range being less than the predetermined value.