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.

Methods, systems, and devices for operating an engine controller in a vehicle for managing motor torque smoothing. One controller is configured to select a periodic disruptive waveform generated over a period of time to approximate that is associated with the vehicle being at idle, determine a first harmonic sinusoid from a group of harmonic sinusoids that reduces the error between an approximated waveform and the disruptive waveform, and initiate a supplemental quantity of torque during the period of time based on the disruption quantity of torque.

A system for early detection of onset of oscillatory instabilities in practical devices is described. The system consists of a measuring device, an instability detection unit and a control unit. The measuring device is configured to generate signals corresponding to the dynamics happening inside the practical device. The instability detection unit is configured to diagnose the stability of the practical device from the signals that are generated by the measuring device. Further, the control unit is configured to control various operating parameters in the practical device based on the information obtained from the instability detection unit.

An engine glow plug disconnection detection method may include: increasing, by a controller, temperature of a plurality of glow plugs by performing a rapid temperature increase mode when an engine start signal of a vehicle is recognized by the controller; determining whether the glow plugs are disconnected and the number of disconnections using an engine start early-stage voltage of the vehicle and a voltage of the vehicle when the rapid temperature increase mode is performed, by the controller; recognizing, by the controller, cylinders of an engine with at least a disconnected glow plug upon determining that one or more glow plugs are disconnected: and storing, by the controller, a number of disconnected glow plugs and information related to corresponding cylinders.

A method adapts an energy supply of a drive system of a vehicle, wherein values of at least a first energy utilization characteristic variable which represents a first energy utilization process in the vehicle are determined, and values of at least one parameter which represents at least one peripheral condition of the energy utilization in the vehicle during the first energy utilization process are determined. A mathematical relationship is determined between at least one or more of the values of the at least one energy utilization characteristic variable and the corresponding values of the parameters of the at least one peripheral condition for the energy utilization is determined, after which a profile data record is made available which contains a data record and/or learning data on the basis of the at least one determined mathematical relationship. As a function of the profile data record which is made available at least one adaptation information item for adapting the energy supply of the drive system of said vehicle for a second energy utilization process is determined and made available, and/or an adaptation information item for adapting the energy supply of the drive system of a second vehicle for an energy utilization process is determined and made available.

In a method and a device for operating an internal combustion engine, with at least one cylinder (Z1-Z4) having a combustion chamber (26), fuel is injected into the cylinder and a logic value (LV_FCUT) is set, in particular for stopping the injection of fuel into the cylinder, The method furthermore has the following steps: depending on a course of the highly time-resolved measurement signal of a rotational speed (N_FAST) of the internal combustion engine, a local maximum value (N_FAST_MAX) of the rotational speed is determined, a rotational speed difference (N_FAST_DIF) between the local maximum value (N_FAST_MAX) and a current measured value (N_FAST_MES) of the rotational speed is determined, and, depending on the determined rotational speed difference (N_FAST_DIF), the logic value (LV_FCUT) is set.

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 apparatus for an internal combustion engine (i) acquires a rotational speed signal correlated with a rotational speed of the internal combustion engine, (ii) extracts, from the acquired rotational speed signal, at least first-order and lower-order than the first-order components of the rotational speed signal, (iii) extracts, from the acquired rotational speed signal, at least an n-th-order component of the rotational speed signal, (iv) determines that no disturbance has occurred when a first-order parameter regarding a magnitude of an amplitude of the extracted first-order and lower-order than the first-order components is smaller than a first threshold, and (v) determines that a disturbance has occurred when the first-order parameter is equal to or larger than the first threshold and an n-th-order parameter regarding an amplitude of the extracted n-th-order component is equal to or larger than a second threshold.

Methods and systems are provided for operating a variable displacement engine that includes a knock control system. Engine knock background noise levels determined during all cylinders operating mode may be determined via two filters that are constructed in parallel. Output of the two filters may be the basis for determining the presence or absence of engine knock.

A state detection system for an internal combustion engine is provided. Rotation waveform variables include information on a difference between cylinders in the rotational speed of a crankshaft during periods in which the respective cylinders generate combustion torque. An obtainment process obtains a value of the rotation waveform variables and a value of a road surface state variable based on an output of a sensor that detects a state of the road surface. A selection process selects, from a plurality of types of mapping data stored in the storage device, the mapping data that is associated with the road surface state variable as the detection mapping. A determination process determines whether the engine is in a predetermined operating state based on an output value of the selected detection mapping that takes the rotation waveform variables as inputs.