Methods and systems are provided for adjusting a location of a fuel injection in response to a substitution rate and a desired EGR flow. In one example, a method may include injecting a first fuel to a combustion chamber via a direct injector positioned to inject directly into the combustion chamber, injecting a second, different, fuel to the combustion chamber via an exhaust port injector positioned to inject toward an exhaust valve of the combustion chamber, and combusting the first and second fuels together in the combustion chamber.

A method of operating an exhaust gas recirculation pump for an internal combustion engine including: providing an EGR pump assembly including an electric motor coupled to a roots device having rotors, the EGR pump operably connected to an internal combustion engine; providing an EGR control unit lined to the EGR pump assembly; providing sensors linked to the EGR control unit; determining if a motor speed is within a predetermined target (step SI), wherein when the motor speed is within the predetermined target then; determining if a motor torque is within a predetermined target (step S2) wherein when the motor torque is within the predetermined target then; determining if a motor temperature is within a predetermined target (step S3) wherein when the motor temperature is within the predetermined target then; maintaining operation of the exhaust gas recirculation pump.

The present invention suppresses the worsening of stability due to a variation in EGR amounts between cylinders in a spark ignition engine. An engine control device for controlling a spark ignition engine equipped with an EGR means for recirculating exhaust gas in a combustion chamber and an air-fuel-ratio detection means for detecting the air-fuel ratio in each cylinder, the engine control device being characterized by being equipped with a means for changing the parameters for ignition control of a rich cylinder, when the air-fuel ratio of cylinders varies and there are richer cylinders and leaner cylinders relative to a prescribed air-fuel ratio during the execution of exhaust gas recirculation by the EGR means.

The purpose of the present invention is to provide an engine control device with which it is possible to minimize decreases in combustion speed even when the EGR rate has been increased. The present invention is an engine control device for: controlling an engine provided with an injector for injecting fuel directly into a cylinder, an ignition device for igniting the injected fuel, and an EGR means capable of recycling combustion gas and varying the EGR rate of the recycling combustion gas; and commanding the injector to perform multiple injections during one cycle, wherein a command is given to perform a control for increasing the injection quantity per compression stroke relative to the total injection quantity in one cycle so that the injection quantity per compression stroke is greater when the EGR rate is high than when the EGR rate is low, and/or a control for increasing the number of injections per compression stroke relative to the total number of injections in one cycle so that the number of injections per compression stroke is greater when the EGR rate is high than when the EGR rate is low.

At the time of increasing an actual intake air amount by increasing a valve overlap period of intake and exhaust valves (2; 3), an actual compression ratio is temporarily decreased to be lower than a steady-state target compression ratio. This makes it possible to increase the valve overlap period without causing interference of the intake and exhaust valves (2; 3) with a piston (8).

Methods and systems are provided for adjusting spark and/or fuel injection to a cylinder based on late combustion, partial burn, or misfire in a neighboring cylinder. In one example, a method may include deactivating spark and fuel injection to a second cylinder receiving exhaust residuals from combustion in a first cylinder, the first cylinder experiencing a misfire or late combustion event. Mitigating actions are performed in the second cylinder before the occurrence of a pre-ignition event.

A control system for an internal combustion engine is provided with a combustion control part, an operating state judging part judging if an engine operating state is a steady state or a combustion noise is a noise transition state where the combustion noise increases over a predetermined allowable noise value when burning fuel by an ignition-assist self-ignition combustion, and an ozone supply control part controlling the amount of ozone supplied to the combustion chamber by the ozone supply system. The ozone supply control part controls the amount of supply of ozone to a predetermined reference amount when the state is judged to be the steady state and controls the amount of supply of ozone to an amount of supply smaller than the reference amount or makes the amount of supply of ozone zero when the state is judged to be the noise transition state.

A control device of an engine is provided. The engine is operated at a high compression ratio, a geometric compression ratio of the engine being 14:1 or higher. The control device includes a fuel injection controller for controlling a fuel injector of the engine to start a fuel injection in a latter half of a compression stroke within an engine operating range where an engine speed is below a predetermined value and an engine load is above a predetermined value, and an ignition controller for controlling an ignition plug of the engine to retard an ignition timing when a timing for the fuel injection controller to start the fuel injection is on a retarding side of a predetermined timing, the ignition timing being retarded based on a retarding amount of the fuel injection start timing from the predetermined timing.

An engine control method includes a step of setting combustion mode in which a first combustion mode in which a mixed gas is combusted by propagating flame or a second combustion mode in which the mixed gas is combusted by self-ignition is selected, a step of setting air-fuel ratio mode in which a lean first air-fuel ratio mode or a second air-fuel ratio mode equal to or richer than a theoretical air-fuel ratio is selected, a step of setting torque reduction in which a torque reduction amount by which a torque generated by an engine is reduced based on a steer angle of a steering wheel, and a suppressing step in which reducing the torque generated by the engine based on the torque reduction amount set in the step of setting torque reduction is suppressed.

Methods and systems are provided for a boosted engine having a split exhaust system. In one example, a method comprises directing exhaust from a first cylinder group to one or more of a pre-compressor location, a post-compressor location, and an exhaust turbine, and directing exhaust from a second cylinder group to one or more of the pre-compressor location, and the exhaust turbine. Engine efficiency and knock control may be enhanced by directing exhaust gases to different locations based on engine operating conditions.