Abstract: A control system and method for controlling an engine includes a control module. The control module includes an evaporation control valve module closing a canister purge valve during a system diagnostic. A torque determination module determines a torque change for an end of the system diagnostic. A torque adjustment module changes an engine torque to a changed torque corresponding to the torque change. The evaporation control valve module opens the purge valve at the end of the diagnostic.

Abstract: A rotational speed parameter is detected in accordance with a rotational speed of the engine. A reference value of the rotational speed parameter is calculated. For each cylinder, an error between the reference value and the rotational speed parameter detected every predetermined crank angle is calculated as a relative speed parameter. For each cylinder, an integrated value is calculated by integrating the relative speed parameters over a predetermined period. For each cylinder, an average value per cylinder of the sum of the integrated values of all the cylinders is calculated. For each cylinder, an error between the integrated value of the cylinder and the average value is calculated. For each cylinder, the output of the engine is controlled in accordance with the error calculated for the cylinder such that variations in the output between the cylinders are suppressed.

Abstract: A spark ignition internal combustion engine in which, during an idling operation, the ignition timing is changed temporarily to the advance side or retard size with respect to the reference ignition timing so that when the engine speed deviates from the target idling speed, the engine speed becomes the target idling speed. When the actual compression ratio at the time of idling is changed, the reference ignition timing at the time of idling is made to move until the ignition timing at which the same generated torque of the engine is obtained.

Abstract: An internal combustion engine has a plurality of cylinders and an exhaust tract into which a mixture which is situated in the respective cylinder is introduced in the respective discharge strokes. A combustion misfire rate is determined as a function of at least one operating variable of the internal combustion engine. A temperature in the exhaust tract is determined as a function of the combustion misfire rate.

Abstract: Embodiments of the invention provide that an ignition is retarded when continuously occurring knocks are detected, while an ignition is not retarded when a singly occurring knock is detected. By detecting the number of occurrences of detection data pieces from a knock sensor 9 stored in a storage unit 14 in a predetermined time period, a distribution of the detection data pieces is created. When one detection data piece having a value not less than a knock determination value is inputted from the knock sensor 9, the distribution of the detection data pieces is checked. For example, when the detection data pieces spread in a wide range, or the knock level voltage of the total detection data pieces is not less than a predetermined value, a retard instruction is outputted.

Abstract: An engine ECU executes a program that includes the steps of: calculating (S204) a median value V(50) and a standard deviation s based on a calculated magnitude value LOG(V); and subtracting (S206) a product of the standard deviation s and a coefficient U(3) from the median value V(50) to calculate BGL. Knocking determination is carried out by comparing a knock magnitude N calculated by dividing the magnitude value LOG(P) by the BGL with a predetermined determination value V(VK). Based on the knocking determination result, ignition timing of the engine is controlled.

Abstract: The invention relates to a method for determining the composition of a fuel blend from a first and at least a second fuel to operate an internal combustion engine with at least one combustion chamber, wherein fuel blends of different composition combust at different optimal ignition angles ZWmax with an optimal degree of efficiency ?max. Provision is thereby made for the ignition angle ZW of the internal combustion engine to be altered, for the degree of efficiency ? of the internal combustion engine or a parameter, which is a function of it, to be determined as a function of the ignition angle ZW and for the composition of the fuel blend to be determined from the change in the degree of efficiency ?? or the parameter, which is a function of it, when the ignition angle ZW is altered and/or from the ignition angle ZW as a function of the degree of efficiency ? or the parameter, which is a function of the degree of efficiency ?.

Abstract: The invention relates to a method having application to combustion control of an internal-combustion engine for real-time estimation of engine combustion parameters from vibratory signals. A vibratory signal representative of the engine vibrations is continuously acquired as a function of the crank angle, from a vibration detector. Real-time filtering of this vibratory signal and real-time estimation of the Fourier decomposition coefficients for the acquired vibratory signal is carried out by inverting the dynamics of the filter which is used. Finally, real-time estimation of combustion parameters allowing the combustion to be qualified is carried out from these coefficients.

Abstract: A an engine management system includes a processor (8) in communication with a memory (10) that contains a program memory (28) containing instructions for the processor to implement a knock detection method. The knock detection method involves firstly sampling a torque sensor (4) that is responsive to an engine crankshaft (5). The torque sensor is sampled a number of times during a combustion stroke of one or more of cylinders (18a, . . . 18d) of the engine (16). The sampled sensor values are processed to calculate a rate of change of the torque signal and knocking is deemed to be indicated in the event of the rate of change exceeding a predetermined value. In a preferred embodiment the processor (8) is further programmed to reduce knocking once it has been detected by adjusting one or more of a number of controllers including a fuel injection controller (34), an ignition controller (12), a throttle controller (13) and an exhaust gas recirculation controller (39).

Abstract: A device for controlling an internal combustion engine which uses, as the fuel, a heavy fuel, a light fuel, an alcohol fuel and a mixture thereof, comprising a heavy fuel/light fuel ratio detector 39 capable of detecting the ratio of the heavy fuel and the light fuel, and an air-fuel ratio detector 41 for detecting the air-fuel ratio of the exhaust gas, wherein the amount of fuel injection is calculated based on the heavy fuel/light fuel ratio detector so that the air-fuel ratio becomes a target air-fuel ratio. The heavy fuel/light fuel ratio detector is diagnosed if it is in an abnormal condition based on a difference between the target air-fuel ratio and the air-fuel ratio detected by the air-fuel ratio detector while the engine temperature is in a particular temperature region. The heavy fuel/light fuel ratio detector can be correctly diagnosed if it is in an abnormal condition even when an alcohol-mixed fuel is used.

Abstract: Ignition timing for a combustion engine may be controlled by determining the roughness of current engine operation, comparing the determined roughness with a control roughness to determine if the determined roughness is within a threshold limit of the control roughness, and changing the ignition timing in a subsequent fuel delivery event as a function of the difference between the determined roughness and the control roughness. Preferably, the ignition timing is changed at least when the determined roughness is not within the threshold limit, although other factors may be taken into account when changing the ignition timing.

Abstract: To improve power performance while avoiding or suppressing surging, an engine control device comprises a VVT mechanism for varying the open/close timing of an intake valve, and the occurrence of surging is determined by comparing an engine rotation variation width with a surge determination threshold. When it is determined that surging has occurred, an ignition timing surge correction amount is set at a value that has been corrected in an advancement direction, and the ignition timing is corrected in the advancement direction by the ignition timing surge correction amount. Further, a VVT surge correction amount by which the open/close timing of the intake valve is corrected using the intake VVT mechanism is set at a value that has been corrected in a retardation direction, and a control current value for operating the intake VVT mechanism is corrected in the retardation direction by the VVT surge correction amount.

Abstract: An idle speed control system for an engine includes an engine speed module that generates an engine speed signal. A piston reciprocation module determines reciprocation periods of each piston of cylinders of the engine based on the engine speed signal. A difference module determines a period difference between each of the reciprocation periods and an idle period associated with a target idle speed. A spark timing module regulates an idle speed of the engine including adjustment of spark timing for each of the cylinders individually based on period differences.

Abstract: In a method for controlling a composition of a fuel/air mixture supplied to an internal combustion engine, which engine has a speed control circuit maintaining an actual rotary speed of the crankshaft within preset limits and a controllable metering device for at least one component of the fuel/air mixture, a disruptive variable is introduced into the valve control circuit at a predeterminable point in time, the activity of an engine speed control circuit is monitored and evaluated immediately after introducing the disruptive variable, and, depending on the evaluation result, at least one parameter having an effect on the operation of the internal combustion engine is adjusted.

Abstract: Ignition timing for a combustion engine may be controlled by determining the roughness of current engine operation, comparing the determined roughness with a control roughness to determine if the determined roughness is within a threshold limit of the control roughness, and changing the ignition timing in a subsequent fuel delivery event as a function of the difference between the determined roughness and the control roughness. Preferably, the ignition timing is changed at least when the determined roughness is not within the threshold limit, although other factors may be taken into account when changing the ignition timing.

Abstract: A damping device comprises a device (4, 7) for determining a mechanical state variable (??MODEL, ??ACTUAL) reproducing the torsion of a drivetrain (3) of an internal combustion engine (1) and an actuator (2) to activate an internal combustion engine (1) with a control variable as a function of the mechanical state variable (??MODEL, ??ACTUAL). It is proposed that the mechanical state variable (??MODEL, ??ACTUAL) be determined by a predictor element (4) that contains a model of the drivetrain (3) and/or the internal combustion engine (1).

Abstract: A rotation speed calculation interval is set near a combustion top dead center of each cylinder of an engine. An interval rotation time necessary for a crankshaft to rotate through the rotation speed calculation interval is calculated as angular speed information of the crankshaft in the rotation speed calculation interval for each combustion stroke of the engine. Engine rotation speed is calculated based on the interval rotation time. The angular speed information of the crankshaft in the rotation speed calculation interval set near the combustion top dead center reflects a combustion state or generated torque. By calculating the engine rotation speed based on the angular speed information, the engine rotation speed highly correlated with the combustion state or the generated torque of the engine can be calculated.

Abstract: A method for controlling an internal combustion engine calculates the generated internal torque for each cylinder on the basis of the signal generated by an angle of rotation sensor for detecting the angle of rotation of the crankshaft, so that a rapid and precise regulation of the torque supplied by the internal combustion engine may be achieved.

Abstract: An ignition circuit is for an internal combustion engine in a handheld portable work apparatus. A combustion chamber (4) is configured in the cylinder (3) of the engine (1) which is delimited by a piston (5) driving a crankshaft (7). A pole wheel (10) revolves with the crankshaft (7) and is assigned to an induction loop (13). The pole wheel periodically changes the magnetic flux in the induction loop. An ignition capacitor (16) is charged by a charge coil (14) of the induction loop and is discharged via a discharge circuit (15) via an ignition coil (17). The ignition coil is connected to a spark plug (19) projecting into the combustion chamber. For achieving a powerful ignition spark, the discharge of the ignition capacitor is prevented by an rpm evaluation circuit (23) when the rpm curve (30) exhibits an rpm change (?n) which exceeds a pregiven threshold value.

Abstract: It is possible to securely detect an erroneous connection between ignition devices and a fuel injection control apparatus by a simple structure without causing any cost increase, in the fuel injection control apparatus of a multiple cylinder engine utilizing ignition signals of ignition devices as reference timings for fuel injection timings.

Abstract: An ignition control device for a two-cycle internal combustion engine that controls an ignition timing for inhibiting detonation while inhibiting an increase in an exhaust pipe temperature, including: map storing means for storing a map that provides a relationship among a throttle valve opening degree and a rotational speed of the internal combustion engine and a delay side allowable limit ignition timing, which is a limit ignition timing on a delay side of the internal combustion engine when the exhaust pipe temperature of the internal combustion engine reaches an allowable upper limit value; arithmetical operation means for arithmetically operating the limit ignition timing by searching the map with respect to the throttle valve opening degree and the rotational speed of the internal combustion engine; and ignition operation stopping means for stopping an ignition operation of the internal combustion engine when an ignition timing of the internal combustion engine is further delayed from the limit ignition

Abstract: If a user presses a clutch pedal to perform gear-shifting operation while a vehicle is traveling, a clutch disc, which has been engaged with a flywheel rotating with an engine, is brought to partial clutch engagement and slides on an end surface of the flywheel to generate friction. Thus, a first phenomenon in which a decreasing rate of the engine rotation speed rapidly increases occurs. Then, a second phenomenon in which the clutch disc is completely disengaged from the flywheel to eliminate the friction and the decreasing rate of the engine rotation speed returns to an original state occurs. If the first and second phenomena are detected successively when neither an engine side nor a power transmission system side transmits power for varying an engine rotation speed, it is determined that the clutch disc is disengaged.

Abstract: A method and a device for operating an internal combustion engine allow an optimal restriction of the ignition angle. In this context, a limit value for an ignition angle is specified as a function of an operating point of the internal combustion engine. The limit value for the ignition angle is corrected as a function of a misfire limit of the internal combustion engine.

Abstract: An engine speed control that avoid undesirable transmission conditions such as clutch chattering. This is done by sensing actual conditions, which are likely to result in the undesirable transmission conditions such as clutch chattering and only changing the engine output when these exact conditions are found. The conditions sensed are the determination of excessive acceleration in engine speed or in the speed of a shaft associated with the engine or the degree of rotational variation or rotational acceleration.

Abstract: A generic technique for the detection of air-fuel ratio (or torque) imbalances in a 4-cylinder engine equipped with either a production oxygen sensor or a wide-range A/F sensor (or a crankshaft torque sensor) is developed. The method is based on a novel frequency-domain characterization of pattern of imbalances and its geometric decomposition into four basic templates. Once the contribution of each basic template to the overall imbalances is computed, templates of opposite direction are imposed to restore air-fuel ratio (or torque) balance among cylinders. At any desired operating condition, elimination of imbalances is achieved within few engine cycles. The method is applicable to current and future engine technologies with variable valve actuation, fuel injectors and/or individual spark control.

Abstract: A combustion state estimating apparatus for estimating the state of combustion in an internal combustion engine includes an angular acceleration calculator that calculates a crank angle acceleration, and a combustion state estimator that estimates the state of combustion in the internal combustion engine based on the crank angle acceleration in a crank angle interval in which an average value of inertia torque caused by a reciprocating inertia mass of the internal combustion engine is substantially zero. Thus, the combustion state estimating apparatus excludes the effect that the inertia torque caused by the reciprocating inertia mass has on the angular acceleration, and therefore is able to precisely estimate the state of combustion based on the angular acceleration.

Abstract: The present invention provides a control system for an internal combustion engine for detecting a torque variation based on a rotational speed of the engine and suppress the torque variation. The system includes a detector for detecting a rotational speed of the engine, a memory for storing a variation pattern of the rotational speed of the engine when a torque of the internal combustion engine is excessive and a controller for calculating a variation component of the rotational speed based on the detected rotational speed, The controller calculates the correlation between the variation component and the variation pattern that is read out from the memory and then determines a torque variation state of the engine based on the correlation.

Abstract: A method for the damping of mechanical vibrations in the drive train of an internal combustion engine by detection of vibration excitations in the drive train, and adjustment of the ignition angle of the internal combustion engine in the event of the occurrence of a vibration excitation in the drive train, in order to damp the vibration in the drive train, the adjustment of the ignition angle taking place in a flexible way.

Abstract: A misfire detector is provided that is accurate even in the case of a disturbance due to causes such as driving on a rough road. The misfire detector is equipped with a crankshaft revolution detector to measure the time period required for the crankshaft of an internal-combustion engine to revolve for a given angle. A signal-processor is also provided for detecting the misfiring of the internal-combustion engine by processing the time period. In one embodiment, the misfire detector has two filters having the same sensitivity to the misfire frequency, and differing in the sensitivity to frequencies adjacent to said misfire frequency. It can be determined that a misfire has occurred if the ratio or difference between the outputs of the two filters stays within a fixed range and one or both of the filters have respective outputs exceeding a threshold value.

Abstract: In a method of controlling an internal combustion engine, at least one operating variable is controlled, a pre-control ignition timing efficiency is formed as a function of operating parameters of the engine and/or external intervention measures, and the pre-control ignition timing efficiency determines the setpoint values of the at least one operating variable. In a transition from a first operating state to a second operating state, the pre-control ignition timing efficiency is varied by a transition function.

Abstract: A number of embodiments of improved engine system control method and apparatus based on operator demand and rate of change in demand that reduce not only the number of components but also decrease the complexity of the electronic system without requiring a throttle position sensor.

Abstract: A method for estimating a cylinder specific performance parameter for a specific cylinder of an internal combustion engine for each firing attempt, which relies on production sensors commonly equipped onboard production vehicles, is disclosed.

Abstract: A processor having an embedded median filter routine, a method of median filtering using a vehicle's CPU, and a misfire detection system for an internal combustion engine with crankshaft acceleration detection means for determining crankshaft acceleration values. In general, the processor is configured to receive new acceleration values and includes a data structure with a data array containing a predetermined number of data fields storing acceleration values in magnitude order. The embedded median filtering routine is configured to identify an oldest in time acceleration value, identify a deletion position in the data array for the oldest in time acceleration value, identify an insertion position in the data array, move selected acceleration values in the data array to vacate the insertion position, insert the new acceleration value in the insertion position, and determine the median value of the acceleration values in the data array.

Abstract: A method and apparatus that permit anti-knock control without the use of separate knock detectors as well as controlling the basic ignition timing from the output of a single engine speed sensor.

Abstract: A processor having an embedded median filter routine, a method of median filtering using a vehicle's CPU, and a misfire detection system for an internal combustion engine with crankshaft acceleration detection means for determining crankshaft acceleration values. In general, the processor is configured to receive new acceleration values and includes a data structure with a data array containing a predetermined number of data fields storing acceleration values in magnitude order. The embedded median filtering routine is configured to identify an oldest in time acceleration value, identify a deletion position in the data array for the oldest in time acceleration value, identify an insertion position in the data array, move selected acceleration values in the data array to vacate the insertion position, insert the new acceleration value in the insertion position, and determine the median value of the acceleration values in the data array.

Abstract: A method for operating an internal combustion engine and a corresponding device are described in which a combustion of a fuel in a fuel-air mixture introduced into a cylinder occurs in at least one cylinder. At least one adjusting device is used to influence at least one physical process, which modifies the distribution of the constituents and/or the overall composition of the fuel-air mixture in the at least one cylinder. If knock occurs, a knock control is used to gradually retard an ignition angle in the at least one cylinder from a fundamental ignition angle by an adjustment angle. When the adjustment of the at least one adjusting device exceeds a specifiable first threshold and/or the change in the at least one physical process exceeds a specifiable second threshold, the adjustment angle is rapidly reduced by increments, the more rapid reduction occurring with a larger increment and/or with a higher frequency of increments.

Abstract: With regard to a stabilization control which is executed while compression stroke injection is executed in an engine warming-up process, an execution period of the stabilization control is limited to a period until when an elapsed time since an engine is started reaches a predetermined time. Accordingly, after the elapsed time reaches a predetermined time, it is possible to suppress an unnecessary increase in a fuel injection amount or unnecessary advance of ignition timing by the stabilization control. Also, when an increase in the temperature of a catalyst is completed in the engine warming-up process, and a fuel injection mode is switched from the compression stroke injection to intake stroke injection, the stabilization control is restarted.

Abstract: The ignition controller includes a crank angle sensor of an internal combustion engine, a cam sensor, and a control unit for controlling the ignition of each cylinder on the basis of a crank angle signal and a cam signal. Upon detecting a change in the engine speed of the internal combustion engine, the control unit has an ignition correcting unit for correcting the ignition energization start timing and the ignition timing in correspondence with that engine speed.

Abstract: The present invention provides a control system for an internal combustion engine for detecting a torque variation based on a rotational speed of the engine and suppress the torque variation. The system includes a detector for detecting a rotational speed of the engine, a memory for storing a variation pattern of the rotational speed of the engine when a torque of the internal combustion engine is excessive and a controller for calculating a variation component of the rotational speed based on the detected rotational speed, The controller calculates the correlation between the variation component and the variation pattern that is read out from the memory and then determines a torque variation state of the engine based on the correlation.

Abstract: A method for controlling incidences of combustion in an unloaded internal combustion engine of a vehicle. The method includes, determining a load-dynamics threshold, detecting an unloaded operating state of the internal combustion engine, detecting an incidence of the load-dynamics threshold being exceeded in the unloaded operating state, and retarding the ignition timing to form a load-dynamics aiming-off allowance that prevents combustion knock.

Abstract: A method and a device for controlling an output variable of a drive unit in the starting phase is described. A controller is provided, regulating the actual value of at least one output variable to a setpoint variable of this output variable which is specified as a function of time. When at least one condition marking entry into the starting phase exists, the setpoint value of the output variable is initialized with the actual value of the output variable.

Abstract: An inertia-related engine speed fluctuation is computed when the engine is rotated without ignition. A load-related engine speed fluctuation is computed when the engine is rotated with ignition and combustion. The inertia-related engine speed fluctuation is indicative of an inertia moment that is variable in accordance with equipments connected with the engine. The load-related engine speed fluctuation is indicative of an engine load. When estimating the engine load, the inertia-related engine speed fluctuation is considered for removing an influence of the inertia moment on the engine load. The estimated engine load is used for controlling the engine. It is possible to consider the inertia moment into an engine control.

Abstract: An improved method and system for the control of an engine system such as the spark timing. The control senses the speed variations either during a portion of a complete cycle and a complete cycle and/or from cycle to cycle in order to determine the load on the engine from preprogrammed maps based upon the engine characteristics. From this load and the speed reading, it is possible to obtain the desired engine control. In addition the timing is set in this method only under certain specified conditions and only in response to certain specific parameters. This not only reduces the costs of the system by reducing the number of sensors, but also permits adjustments to be made more rapidly.

Abstract: A method and apparatus for controlling timing of an internal combustion engine having a piston located in a cylinder. The method and apparatus includes determining a first angular position of a crankshaft at a first location along a longitudinal axis of the crankshaft, determining a second angular position of the crankshaft at a second location along the longitudinal axis, determining a level of deformation of the crankshaft as a function of a difference between the first and second angular positions, determining an actual position of the piston as a function of the crankshaft deformation, comparing the actual piston position to a desired piston position, and controlling timing of an event to initiate combustion in the cylinder as a function of a difference between the actual and desired piston positions.

Abstract: In order to control vehicle shuffle, ie undesired fore and aft oscillations of the vehicle, the invention discloses a method comprising the steps of: continuously sensing the speed of the vehicle motor and producing a signal representing the speed analysing the speed signal determining a mean value for the speed signal identifying fluctuations from the mean value filtering the signal to remove the mean value and to retain the fluctuations applying a phase change to the filtered signal applying a deadband such that signals below a predetermined magnitude are ignored amplifying the filtered and phase changed signal resulting from the deadband application, and supplying the filtered, phase changed and amplified signal to a controller which controls the torque output of the vehicle motor.

Abstract: A generic technique for the detection of air-fuel ratio or torque imbalances in a three-cylinder engine equipped with either a current production oxygen sensor or a wide-range A/F sensor, or a crankshaft torque sensor, is disclosed. The method is based on a frequency-domain characterization of pattern of imbalances and its geometric decomposition into two basic templates. Once the contribution of each basic template to the overall imbalances is computed, templates of same magnitude of imbalances but of opposite direction are imposed to restore air-fuel ratio (or torque) balance among cylinders. At any desired operating condition, elimination of imbalances is achieved within few engine cycles. The method is applicable to current and future engine technologies with variable valve-actuation, fuel injectors and/or individual spark control.

Abstract: A misfire detection apparatus for an internal combustion engine determines misfire based on first and second variation amounts calculated based on variations of rotational speed of the internal combustion engine. A second variation amount is calculated, and it is determined whether or not a value obtained by multiplying the second variation amount by −1 is greater than a misfire determination level C1, and if the value is less than the level, process proceeds calculates a final variation amount. If the value is greater than a predetermined value, the process determines the final variation amount from the first variation amount. When the processing has been completed, the process determines whether or not the final variation amount is equal to or greater than the misfire determination level.

Abstract: An apparatus for detecting a condition of the burning in an internal combustion engine includes a burning-parameter controlling device for controlling a burning parameter operating on the burning in the internal combustion engine. A burning-condition detecting device operates for, in cases where the burning parameter is changed by the burning-parameter controlling device, sampling prescribed information for detecting a burning condition.

Abstract: An improved method and system for the control of an engine fuel injection system. The control senses the speed variations either during a portion of a complete cycle and a complete cycle and/or from cycle to cycle in order to determine the load on the engine from preprogrammed maps based upon the engine characteristics. From this load and the speed reading, it is possible to obtain the desired engine fuel injection control. This not only reduces the costs of the system by reducing the number of sensors, but also permits adjustments to be made more rapidly.

Abstract: A method and system for controlling an automotive internal combustion engine having NVH feedback uses NVH signals which are processed and compared with human threshold values to determine whether an engine control parameter such as idle speed needs to be adjusted so as to mitigate unwanted noise, vibration, and harshness.