Abstract: It is disclosed an electronic device to control an ignition coil of an internal combustion engine, comprising a high-voltage switch, a driving unit, a bias circuit and an integrating circuit. The high-voltage switch is connected in series with a primary winding of a coil. The driving unit is configured to control the closing and opening of the high-voltage switch. The integrating circuit is interposed between the bias circuit and a reference voltage. The integrating circuit comprises an integrating capacitor connected in series to the bias circuit and connected between the bias circuit and the reference voltage. The integrating capacitor is configured to maintain a substantially null charge during a phase of measurement of a ionization current as to measure a substantially null value of an integral of the ionization current, in the case of a misfire of the comburent-combustible mixture.

Abstract: A controller and a control method for an internal combustion engine, and a memory medium are provided. In a first combustion cylinder, first combustion is caused by control circuitry when the engine is restarted from a state where fuel combustion in cylinders is suspended. An automatic stopping process suspends the fuel combustion in the cylinders and controls a throttle valve to a closed state when a predetermined condition is satisfied. A first calculation process calculates an amount of fuel injected into the first combustion cylinder based on a position of the piston in the first combustion cylinder in a case where a rotation speed of a crankshaft obtained when the restart was requested is zero. A second calculation process calculates the injection amount based on the rotation speed in a case where the rotation speed obtained when the restart was requested is higher than zero.

Abstract: Provided is a load drive device for controlling a fuel injection device for a vehicle engine and capable of checking an operation of the fuel injection device with high reliability without actually injecting fuel before starting the engine.

Abstract: An electrode wear amount predicting system of a spark plug, includes: at least one ignition coil that includes a primary coil and a secondary coil; a spark plug that generates a spark discharge by a discharge current generated by the ignition coil and includes a center electrode and a ground electrode; a sensing portion measuring a current applied to the primary coil; and a controller that determines a wear state of the center electrode and the ground electrode according to an amount of the current applied to the primary coil detected by the sensing portion when an electrode wear amount predicting condition is satisfied.

Abstract: An apparatus obtains waveforms representing measurements of a physical characteristic of a machine's operation and performance results of the machine corresponding respectively to the waveforms, each of the performance results being indicative of the machine's performance under conditions at which the measurement represented by the corresponding waveform was made. The apparatus calculates, for each of at least interval associated with each of the waveforms, an influence value that represents a degree of influence of the waveforms on the performance results over the interval.

Abstract: A method for predicting failure in a cylinder of a multi-cylinder engine is provided. Each cylinder has an associated pressure sensor to provide a signal indicative of pressure in the cylinder. The method includes identifying whether there is a non-fueling interval associated with any of the cylinder on the engine. The method includes determining at least one of parameters such as an indicated mean effective pressure, a peak cylinder pressure, a total heat released, or a total duration of heat released over a combustion cycle for the cylinder. The method includes comparing the at least one of the parameters with predefined threshold value, determining whether any of the parameters exceeds the predefined threshold value, and generating a signal indicating the impending cylinder failure if at least one of the parameters exceeds the corresponding predefined threshold value.

Abstract: An internal combustion engine includes a method for operating including, determining, using an accelerator pedal position sensor, an operator request for power and determining an engine operating point based upon the operator request for power. A motored-cylinder temperature is determined based upon the engine operating point, and a knock-limited combustion phasing point is determined based upon the motored-cylinder temperature and the engine operating point. Engine operating parameters associated with achieving the knock-limited combustion phasing point are selected. Operation includes controlling, by a controller, engine control states in response to the engine operating parameters associated with achieving the knock-limited combustion phasing point and the operator request for power.

Abstract: An engine control system and method of reducing knocking combustion in a spark-ignited internal combustion engine having exhaust gas recirculation by controlling engine timing based on detection of a misfire in an engine cylinder. The engine control system determines a number of combustion cycles indicative of an amount of time that will pass before misfire gas from the detected misfire will be recirculated to a combustion chamber of any cylinder of the internal combustion engine, and the engine control unit reduces or prevents knocking combustion by adjusting the ignition timing of at least one subsequent combustion cycle after the determined number of combustion cycles have occurred since the misfire was detected.

Abstract: An engine includes at least one spark plug, an ignition advance management device to determine and to apply an optimum ignition advance of the spark plug, and an exhaust gas recirculation device equipped with a gas recirculation control valve. A control device for the internal combustion engine includes a first actuator to force opening and closing of the control valve, a map in which are stored theoretical ignition advance values as a function of engine speed and engine load, a first calculator to calculate a diagnostic criterion as a function of the theoretical ignition advance determined from the map and the optimum ignition advance, and a comparator to compare the diagnostic criterion to a control valve failure threshold.

Abstract: A system includes a controller configured to receive a signal acquired by the at least one knock sensor coupled to a reciprocating device, to sample the received signal, to analyze the sampled signal, and to utilize standard quality control (SQC) techniques to perform real-time diagnostics on the reciprocating device based on the analyzed signal.

Abstract: In order to solve a problem that in an internal combustion engine in which abnormal combustion (knocking or an accidental fire) of an engine is detected from an ion signal, the setting of an abnormal combustion determination threshold value under a transient condition in which an engine operating state abruptly changes is difficult to thereby cause erroneous determination, the present invention is an engine control device provided with an ion signal detection means for detecting ions generated during combustion, and provided with an abnormal combustion determination means for determining knocking or an accidental fire according to an ion signal detected by the detection means, the engine control device being characterized by being provided with an in-cylinder temperature estimation means for estimating the in-cylinder temperature in a normal combustion cycle under a current operating condition of the engine, and by setting the knocking determination threshold value or accidental fire determination threshold v

Abstract: A variety of methods and arrangements for detecting misfire in a skip fire engine control system are described. In one aspect, a window is assigned to a target firing opportunity for a target working chamber. A change in an engine parameter is measured during the window. A determination is made as to whether a firing opportunity before the target firing opportunity is a skip or a fire and/or whether a firing opportunity after the target firing opportunity is a skip or a fire. Based at least in part on this skip/fire determination, a determination is made as to whether the target working chamber has misfired. In various embodiments, if the target working chamber is identified as persistently misfiring, the firing sequence is modified so that the target working chamber is deactivated and excluded from the firing sequence. In still other embodiments, a torque model is used to detect engine-related problems.

Abstract: Methods and systems are provided for addressing pre-ignition that may be induced in response to actions taken to mitigate a cylinder misfire. An amount of engine load limiting applied may be adjusted to reduce the likelihood pre-ignition while also addressing component over-temperature issues. By limiting an engine load while shutting off fuel in a misfiring cylinder, and while combusting a lean air-fuel mixture in the remaining cylinders, pre-ignition induced by the misfire-mitigating lean combustion conditions can be reduced.

Abstract: A spark ignition type internal combustion engine 1 causes a spark discharge generated between a center electrode 22 and a ground electrode 23 and an electric field generated via an antenna 16 facing inside of a combustion chamber 6 to interact to generate a plasma and ignite a fuel-air mixture. A combustion state determination device used in the spark ignition type internal combustion engine 1 determines a combustion state of the internal combustion engine 1 by comparing a strength of a reflected wave of an electromagnetic wave applied into the combustion chamber 6 from the antenna 16 with a threshold of a combustion state derived in advance by an experiment. This allows for the determination of the combustion state of the spark ignition type internal combustion engine that causes the spark discharge and the electric field to interact to generate the plasma and ignite the fuel-air mixture.

Abstract: A condition of an engine is diagnosed based on information provided by signals from speed sensors associated with the engine or other signals associated with a generator operationally connected to the engine. Different types of degradation are distinguished based on discerning characteristics within the information. Thus, a degraded engine component can be identified in a manner that reduces service induced delay.

Abstract: Methods and systems are provided for an engine. A condition of the engine may be diagnosed based on a combustion torque profile of the engine estimated using signals from a generator operationally connected to the engine and/or other signals associated with the engine. Different types of degradation may be distinguished based on discerning characteristics within the estimated combustion torque profile data. Thus, a degraded engine component may be identified in a manner that reduces service induced delay.

Abstract: A system for monitoring and cleaning a spark plug is disclosed. In one example, an amount of carbonaceous soot at the center electrode ceramic of the spark plug is determined in response to a voltage of a sense resistor that is in electrical communication with the spark plug. The system may institute spark plug cleaning after carbonaceous soot is detected so that the possibility of engine misfire may be reduced.

Abstract: Disclosed is a control device that is used for an internal combustion engine and capable of periodically varying an air-fuel ratio while keeping torque generated by the internal combustion engine at a target torque. The control device can periodically vary a target air-fuel ratio and controls a fuel injection amount in accordance with the target air-fuel ratio which periodically varies. Further, the control device sets an air amount control torque in accordance with the target torque and calculates a target air amount for achieving the air amount control torque at a predetermined virtual air-fuel ratio. The control device then provides air amount control in accordance with the target air amount and calculates an air amount that is estimated to be achieved by the air amount control.

Abstract: A method comprises steps for reconstructing in-cylinder pressure data from a vibration signal collected from a vibration sensor mounted on an engine component where it can generate a signal with a high signal-to-noise ratio, and correcting the vibration signal for errors introduced by vibration signal charge decay and sensor sensitivity. The correction factors are determined as a function of estimated motoring pressure and the measured vibration signal itself with each of these being associated with the same engine cycle. Accordingly, the method corrects for charge decay and changes in sensor sensitivity responsive to different engine conditions to allow greater accuracy in the reconstructed in-cylinder pressure data.

Abstract: A method is provided for controlling an internal combustion engine. The method includes, but is not limited to the step of measuring in-cylinder pressure of an expansion phase of a combustion cycle of a cylinder of the internal combustion engine and measuring in-cylinder pressure of a compression phase of the combustion cycle of the cylinder of the internal combustion engine. A difference between a polytrophic expansion phase constant of the cylinder of the internal combustion engine and a polytrophic compression phase constant of the cylinder of the internal combustion engine is then determined using the measured expansion phase pressure and the measured compression phase pressure. A misfiring of the cylinder is later detected using the determined difference.

Abstract: In a method and a device which allow determination of the combustion lambda value of an internal combustion engine having at least two combustion chambers without using a lambda sensor, a predetermined first fuel quantity is metered to the first combustion chamber and a predetermined second fuel quantity is metered to the second combustion chamber, the first fuel quantity is reduced by a predetermined amount and the second fuel quantity is increased by the same predetermined amount. A first engine noise, associated with the first combustion chamber, and a second engine noise, associated with the second combustion chamber, are determined. The combustion lambda value is determined based on the first engine noise value and second engine noise value.

Abstract: The method comprises operating an engine and collecting a real-time accelerometer signal from an accelerometer sensor. The real-time accelerometer signal is digitized and filtered to isolate data in a frequency range associated with combustion to produce a filtered signal data set. The filtered signal data set is integrated to produce an integrated signal data set, and misfire is detected by comparing the integrated signal data set with a predetermined reference data set associated with the same operating point. The apparatus is a control system for an engine that comprises an accelerometer sensor mounted to the engine; a look-up table in which is stored predetermined reference data sets, in association with predetermined operating conditions; and an electronic controller programmed to carry out the foregoing method.

Abstract: The present invention is a method for reducing misfire in a cylinder of an internal combustion engine. The method includes detecting a misfire event frequency that is equal to or greater than a first predetermined value, determining a pulse-width signal for a fuel injector associated with the cylinder during the misfire event, increasing the pulse-width signal if the misfire event is frequency is below a second predetermined value, and reducing the increase in the pulse-width signal if the misfire event frequency is below the first predetermined value.

Abstract: In a method for diagnosing an internal combustion engine having first and second fuel injectors, if a misfire is detected, the following steps are performed in sequence: a first fuel quantity of the fuel is introduced only by the first fuel injector; a check is performed to determine whether a misfire results from the introduction of a first fuel quantity in the first step; a second fuel quantity of the fuel is introduced only by the second fuel injector; a check is performed to determine whether a misfire results from the introduction of the second fuel quantity in the third step; and an engine error is diagnosed if a misfire was detected in the second or in the fourth step.

Abstract: An engine control system includes a disturbance module, a misfire threshold determination module, a disturbance ratio module, and a spark control module. The disturbance module determines a disturbance value for a past combustion stroke of a cylinder based on rotation of a crankshaft. The misfire threshold determination module determines a jerk value indicative of a misfire within the cylinder. The disturbance ratio module determines a disturbance ratio for the past combustion stroke based on the disturbance value and the jerk value. The spark control module determines a spark timing for a future combustion stroke of the cylinder, determines a spark timing correction for the future combustion stroke based on the disturbance ratio, determines a corrected spark timing based on the spark timing and the spark timing correction, and generates spark during the future combustion stroke based on the corrected spark timing.

Abstract: The present invention is an operation control method on the basis of an ion current in an internal combustion engine, the method comprising a step of detecting the ion current generated within a combustion chamber 30 so as to control an operating state of the internal combustion engine 100 on the basis of a state of the detected ion current, wherein a control at an engine start point in time on the basis of the state of the ion current is stopped for predetermined cycles just after the engine start.

Abstract: In a motor vehicle with idle stop function, upon satisfaction of preset engine restart conditions (step S205), automatic engine restart control refers to a preset map representing a variation in amount of fuel Q1, which is to be initially injected into a cylinder Cyin stopping in an intake stroke, against the piston stop position Pin of the cylinder Cyin, and specifies the amount of fuel Q1 corresponding to the detected piston stop position Pin of the cylinder Cyin (step S220). The automatic engine restart control then controls an injector to inject the specified amount of fuel Q1 into an intake port of the cylinder Cyin (step S230). Under the condition that the piston stop position Pin of the cylinder Cyin suggests low gas intake performance, the increased amount of fuel Q1 is injected into the intake port of the cylinder Cyin. This arrangement desirably reduces a misfire rate at the timing of first combustion and thereby improves the startability of an engine.

Abstract: A first ignition cylinder that performs ignition first is set based on an engine stop position in automatic start. Existence/nonexistence of a misfire in the first ignition cylinder is determined based on whether a difference ?Ne between engine rotation speed at a predetermined crank angle in an interval from timing immediately before the ignition to timing immediately after the ignition of the first ignition cylinder (e.g., at TDC of first ignition cylinder) and engine rotation speed at a predetermined crank angle before ignition of a second ignition cylinder (e.g., at TDC of second ignition cylinder) is equal to or smaller than a predetermined misfire determination threshold value Nef. When misfire time number of the first ignition cylinder exceeds a predetermined value, fuel supply to the first ignition cylinder is prohibited and the automatic start is started from the second ignition cylinder.

Abstract: A failure diagnosis apparatus for a vehicle is disclosed. The apparatus includes a diagnosis processing section for executing failure diagnosis processing on a device of the vehicle to generate a diagnosis result. The apparatus also includes a data managing section for managing data of the diagnosis result. After an execution condition is met for failure diagnosis, the diagnosis processing section outputs an execution demand to the data managing section for the failure diagnosis processing. In response to the execution demand, the data managing section outputs an execution permission to the diagnosis processing section for the failure diagnosis processing. Also, after the execution condition is met for the failure diagnosis, the diagnosis processing section starts executing the failure diagnosis processing regardless of whether the execution permission has been outputted by the data managing section. A method of failure diagnosis is also disclosed.

Abstract: Engine misfire is detected by using threshold values that vary depending on whether damping control is executed. First threshold values are adopted at the setting of a gearshift position to a drive position or a park position where damping control is performed to reduce the vibration of an engine. Second threshold values are adopted at the setting of the gearshift position to a neutral position where the damping control is not performed, the second threshold values being greater than the first threshold values. Engine misfire detection is carried out by processing using the first and second threshold values.

Abstract: In an internal combustion engine including a flywheel damper, an operation range in which misfire detection is affected by the flywheel damper is set in advance. Whether or not an operation state of the internal combustion engine is within an operation range affected by the flywheel damper is determined. When the operation state is within the operation range affected by the flywheel damper, for example a cylinder specifying process specifying a misfiring cylinder is stopped. By such processing, erroneous detection attributed to irregular rotation fluctuation behavior caused by the flywheel damper can be avoided, and misfire detection performance can be improved.

Abstract: Provided is an engine control apparatus equipped with a three-way catalyst for purifying exhaust gas, a unit for calculating an operational state based on outputs from various sensors, a unit for calculating a fuel injection amount, a unit for driving an injector, a unit for calculating an actual misfire ratio, a catalyst damage determining misfire ratio calculating unit for calculating a misfire determining ratio, a catalyst damaging misfire determining unit for cutting off a supply of fuel when it is determined that a damage-causing misfire state has arisen, a unit for storing an actual misfire ratio at a time when it is determined that the damage-causing misfire state has arisen, and a unit for making a recovery from the cutoff of the fuel supply when the misfire determining ratio has become larger than the misfire ratio at the time of the determination that the damage-causing misfire state has arisen.

Abstract: An ignition device, including: an ignition coil (1) having a primary coil and a secondary coil; a switching element (5) for causing a primary current to be conducted through and shut off from the primary coil of the ignition coil; a waveform shaping circuit (6) for shaping a waveform of an ignition signal transmitted from an outside through a signal line to supply a conduction signal thus obtained to the switching element; ion current detecting means (8, 9) connected to the secondary coil of the ignition coil, for detecting an ion current flowing through the secondary coil; and ion signal generating means (10, 11, 12) for outputting an ion signal, which indicates the ion current detected for a predetermined period after the conduction signal of the waveform shaping circuit has been turned off, to the outside through the signal line while invalidating the conduction signal from the waveform shaping circuit.

Abstract: A device for ignition control in a cylinder of an internal combustion engine includes an ignition coil which has a connected primary winding and a secondary winding, which is connected to a spark plug. The device also includes an ignition control unit, which connects the primary winding by way of a first line and is connected to the secondary winding by way of a second line. The second line supplies an ionic current signal emitted from the spark plug to the ignition control unit. A single line is used as the first line and the second line. The active direction of the line can be adjusted by different levels of voltage applied to the line.

Abstract: Presented is a device that provides a correction factor to compensate for varying fuel and air properties in an ion signal sensed in combustion chamber of reciprocating and continuous combustion engines, on a predetermined basis during the combustion of conventional petroleum-based fuels, other alternate fuels, and renewable fuels. The device uses an ion current reference sensor device and a processing module to provide a correction factor to the ion signal(s). The ion current reference sensor device is positioned near the chamber(s) of the engine and fuel provided to the chamber(s) is routed to provide a diffusion flame and the resultant ion current from the flame is measured and provided to the processing module at discrete intervals during the combustion process. Alternatively, a pre-mixed flame is used. The processing module provides a scaling factor to be applied to the ion signal and/or calibration points used to detect combustion conditions.

Abstract: A system for, and a method of, obtaining, for analysis, from a subject internal combustion engine, real-time engine knock data involving assessing, as a positive indication of engine knock behavior, whether the energy-content value represented in at least one selected, knock-relevant frequency-domain spectral bin which is present in a frequency-domain energy-content spectrum derived from acquired engine operating data of a type expected to contain evidence of engine knock behavior exceeds that of a pre-selected energy threshold value.

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: This feature of the present invention comprises a closed loop which uses estimated MBT timing criteria and ignition diagnostics (knock, partial-burn, and misfire) to control engine ignition. When the engine is not knock limited, it operates at its MBT timing. When the engine is knock limited, the engine runs at its inaudible knock limit. When the engine is misfire/partial-burn limited, the engine is maintained at its misfire/partial-burn limit. Three different embodiments of the closed loop MBT timing control architecture are disclosed: a cylinder-by-cylinder control, an average control and a mixed control.

Abstract: In a first preferred embodiment, the present feature of the invention multiplexes both the ionization and driver current feedback signals into one signal, thus reducing cost and making coil packaging easier. The multiplexed signal first outputs the ionization detection signal and then replaces the ionization signal with the charge current feedback signal when the charge command Vin is enabled. In other words, the multiplexed feedback signal outputs the ionization feedback signal and switches to the charge current feedback signal when the charge command Vin is active. In a second preferred embodiment, the present feature of the invention comprises a method and apparatus to multiplex the ignition driver gate signal with both the ignition coil charge current feedback signal and the ionization signal, thus reducing the package pin count by two.

Abstract: An apparatus and method to detect abnormal combustion conditions for use as a feedback control of an EGR (Exhaust Gas Recirculation) controlled reciprocating engine using ionization signals is presented. The system receives a succession of ionization signals for successive cycles of a running engine and processes a plurality of related ionization signals for signal stability. The ionization signals are checked to determine if an abnormal combustion condition such as knock or misfire has occurred. The variation of an ionization signal that changes with respect to an engine parameter over a combustion event of the reciprocating engine is measured and a floating bounded space is associated with the ionization signal. An indication that the abnormal combustion condition has been detected is provided if a portion of the ionization signal is within the floating bounded space.

Abstract: In a method for reducing NOx in the exhaust gas of an externally ignited, explosion-type internal combustion engine that is operated at a lean fuel/air ratio of ?>1 and has a motor control device for controlling ?, the ? value is slidingly controlled as a function of an average mass temperature in the combustion chamber of the externally ignited, explosion-type internal combustion engine, wherein for a low average mass temperature ? is decreased and for a high average mass temperature ? is increased such that the internal combustion engine is operated in any operational state close to the misfiring limit, and thereby, with the most minimal NOx emission possible.

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: A method and system for a misfire detection acquires (301) a series of acceleration data (302) representative of acceleration behavior of an engine. The data is sampled (304) to obtain acceleration data samples at a rate sufficient to obtain up to fourth-order perturbations of the data. The samples are filtered (322) to provide bandwidth limited samples, which are provided to at least two channels (325, 329). The samples are pattern matched (332) in a first channel to enhance harmonic phenomena and pattern canceled (330) in a second channel to enhance random phenomena. Hard and random misfires are detected (334) dependent on a magnitude of the filtered acceleration data samples. Preferably, a third channel (335) is added to detect multiple misfires.

Abstract: This invention relates to a method in connection with engine control, wherein a combustion feedback signal is derived by measuring one or more combustion related parameters during a chosen time period of a first combustion cycle, for control of a possible fault, wherein at least one reference feature for said parameters has been determined previously, and comparing said measured combustion feed back signal with said reference feature for automatic adaptation of at least one combustion related variable during a forthcoming combustion cycle wherein at least one reference features for each one of at least two different fault situations having been determined previously, and that a diagnosis 3 of said first combustion cycle is performed on the basis of said combustion feedback signal being processed and compared (T1-Tn) with each one of said reference features, the result of which is analysed by a decision logic, whereafter a diagnosis (D) is established by means of which one or more variables in a forthcoming co

Abstract: In a system for detecting misfire for an internal combustion engine wherein ionization current that flows following the discharge current is detected and integrated during a period (gate) and occurrence of misfire of the engine is detected based on the integrated value, a processing delay circuit is provided which inputs at least one of the discharge current or the ionization current and based on the inputted current, delays starting of the period by a time point which is not earlier than termination of the discharge current. With this, the system is unaffected by fluctuation in ignition coil discharge period, various kinds of noise and the like, and can therefore ensure accurate misfire detection by preventing erroneous detection owing to such causes.

Abstract: An apparatus and method to detect abnormal combustion conditions for use as a feedback control of an EGR (Exhaust Gas Recirculation) controlled reciprocating engine using ionization signals is presented. The system receives a succession of ionization signals for successive cycles of a running engine and processes a plurality of related ionization signals for signal stability. The ionization signals are checked to determine if an abnormal combustion condition such as knock or misfire has occurred. The variation of an ionization signal that changes with respect to an engine parameter over a combustion event of the reciprocating engine is measured and a floating bounded space is associated with the ionization signal. An indication that the abnormal combustion condition has been detected is provided if a portion of the ionization signal is within the floating bounded space.

Abstract: An apparatus and method to detect and control the combustion quality of a lean burn reciprocating engine using ionization signals is presented. The system receives a succession of ionization signals for successive cycles of a running engine and processes a plurality of related ionization signals for signal stability. A start point and peak of the ionization signal is identified, using an initial current level for all of the signals. A geometric parameter is associated with the ionization signal that relates the start point to the peak. The geometric parameter is compared against a reference geometric parameter related to a desired combustion quality relating to a lambda greater than 1.4. A control parameter of the engine is adjusted such that an error difference between the geometric parameter and the reference geometric parameter is minimized. The ionization signals are checked to determine if an abnormal combustion condition such as knock or misfire has occurred.

Abstract: A combustion state during the initial stage after ignition is detected, and based on the detected combustion state, it is judged whether or not incomplete combustion has occurred, and when it is judged that incomplete combustion has occurred, an ignition signal is output so as to perform the re-ignition immediately.

Abstract: An apparatus and method to detect and control the combustion quality of a lean burn reciprocating engine using ionization signals is presented. The system receives a succession of ionization signals for successive cycles of a running engine and processes a plurality of related ionization signals for signal stability. A start point and peak of the ionization signal is identified, using an initial current level for all of the signals. A geometric parameter is associated with the ionization signal that relates the start point to the peak. The geometric parameter is compared against a reference geometric parameter related to a desired combustion quality relating to a lambda greater than 1.4. A control parameter of the engine is adjusted such that an error difference between the geometric parameter and the reference geometric parameter is minimized. The ionization signals are checked to determine if an abnormal combustion condition such as knock or misfire has occurred.

Abstract: In a first preferred embodiment, the present feature of the invention multiplexes both the ionization and driver current feedback signals into one signal, thus reducing cost and making coil packaging easier. The multiplexed signal first outputs the ionization detection signal and then replaces the ionization signal with the charge current feedback signal when the charge command Vin is enabled. In other words, the multiplexed feedback signal outputs the ionization feedback signal and switches to the charge current feedback signal when the charge command Vin is active. In a second preferred embodiment, the present feature of the invention comprises a method and apparatus to multiplex the ignition driver gate signal with both the ignition coil charge current feedback signal and the ionization signal, thus reducing the package pin count by two.