Abstract: An apparatus and method to detect abnormal combustion conditions for use as a feedback control 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. 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 lean burn reciprocating engine operating with an air to fuel ratio corresponding to a lambda (&lgr;) greater than 1.4 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: This feature of the present invention comprises an ignition diagnostics and feedback control system based upon detected ionization current in an individual cylinder. The system is divided into two subsystems: an ignition diagnostics subsystem and an ignition feedback control system subsystem. The ignition diagnostics subsystem comprises an ignition system diagnostics, a misfire detector, a knock detector, and a robust multi-criteria minimum timing for best torque MBT timing estimator. The ionization feedback control subsystem comprises five main subsystems: a closed loop cold start retard spark control using ionization feedback, a closed loop MBT timing control using ionization feedback, a closed-loop individual cylinder air to fuel ratio balancing control system, an optimal wide open throttle air/fuel ratio control, and an exhaust gas control using a spark plug ionization signal.

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: 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: The method serves for input signal correction of a misfire detection function and for cylinder equalization in an internal combustion engine, especially of a motor vehicle. Here, it is provided that a control for the input signal correction (10) and a control of the cylinder equalization (11) are activated alternatively by an alternative circuit unit (12).

Abstract: An ignition apparatus including a primary and a secondary winding for producing a spark voltage, an ion current detection circuit for producing an ion current signal, a slope detector and a knock detector. The slope detector determines when the ion current signal exhibits a slope indicative of a time period when knock is likely to occur, and de-asserts a knock reset signal. The knock reset signal holds the knock detector in reset, thus disallowing or masking the processing of signals by the knock detector that may be mistaken for knock.

Abstract: The present invention relates to a method for detecting combustion misses in a multi-cylinder internal combustion engine, having at least one first engine control unit which controls at least the injection and firing of a first subset of the cylinders of the internal combustion engine, and having at least one further engine control unit which controls the injection and firing of a further subset of cylinders and in which the detection of combustion misses for the first and the further subset of cylinders is additionally carried out; the control units using an engine control program which is interrupted by interrupt routines, in phase-synchronism with the rotational movement of the crankshaft, in which at least the data required for the injection and firing are processed; and in which method the detection of combustion misses is based on establishing and evaluating crankshaft segment times in which the crankshaft covers an associated circle-segment angle range; and the crankshaft segment times likewise being e

Abstract: A combustion state detection apparatus for an internal combustion engine has a detection period limit section, which limits a detection period of an ion current processed in misfire detection section or knock detection section.

Abstract: Electronic control apparatus including a V-type multi-cylinder internal combustion engine having right and left banks of cylinders 1a and 1b, a crank-angle detecting device 12 for a camshaft of one bank 1a and which outputs a rotational-angle signal, a cylinder determination device 14 for generating a determination signal of which cylinder is to be ignited, an intake-air volume measuring device 4 for measuring an intake-air volume, and an ECU 18 for inputting the intake-air volume, the rotational-angle signal and the cylinder determination signal to calculate a rotational speed and ignition timing. The electronic control apparatus is configured so that ECU 18 inputs the rotational-angle signal from the crank-angle detecting device 12 and predicts a signal period of the next time from a state of change in the signal period of the same bank and sets ignition timing of the next time based on this predicted result.

Abstract: An engine control system and method include determining which engine cylinder is performing at a level differently than a majority of the other cylinders. Whenever a cylinder output is below that of the other cylinders, an engine performance variable, such as the spark angle, preferably is adjusted to bring the cylinder indicated mean effective pressure into conformance with that of the other cylinders. By adjusting the individual cylinder performance variable, engine performance is brought to a desired level of smoothness, especially under conditions such as engine idle.

Abstract: A control system for an internal combustion engine is provided which comprises detecting means for detecting a discharge current flowing between electrodes of a spark plug when a high voltage for ignition is applied to the spark plug, judging means for judging whether or not the spark plug is fouled on the basis of the discharge current, and inhibiting means for inhibiting the progress of spark plug fouling when the spark plug is judged fouled. A method carried out by the control system is also provided.

Abstract: The invention is a strategy to detect spark plug misfires in a multiple spark plug per cylinder internal combustion engine (ICE). The present invention monitors spark plug misfires for each plug within each cylinder and initiates diagnostic fault code setting and failure mode actions such as modifying spark timing and the air/fuel ratio for the cylinder with the misfiring plug to optimize emissions and performance. The strategy modifies spark timing (such as spark retard) of a spark plug not under test but within the same cylinder of the tested spark plug and tests the tested spark plug for misfire (such as changes in crankshaft velocity or acceleration). The amount of spark retard invoked can be a calibrated value such as 30 or 50 degrees off Maximum Brake Torque (MBT) timing. The invention provides improvement over the prior art in that the strategy does not require the complete disabling of a spark plug within the same cylinder as the tested spark plug.

Abstract: An engine control system and method include determining which engine cylinder is performing at a level differently than a majority of the other cylinders. Whenever a cylinder output is below that of the other cylinders, an engine performance variable, such as the spark angle, preferably is adjusted to bring the cylinder indicated mean effective pressure into conformance with that of the other cylinders. By adjusting the individual cylinder performance variable, engine performance is brought to a desired level of smoothness, especially under conditions such as engine idle.

Abstract: A method of detecting combustion misfires in an internal-combustion engine, includes the following steps: variably actuating valve drives of the engine by an electronic engine control; performing a load-dependent control with the control system by a cylinder-control program; the load-dependent control includes the step of reducing power in at least one cylinder by separately affecting ignition and fuel supply thereto; detecting, in the control system by the cylinder-control program, the cylinder of reduced power with a cylinder-identification signal; at predeterminable intervals detecting, from signals obtained in the preceding step, resulting deviations of predetermined operating data as normal operation; detecting, as combustion misfires, deviations of the predetermined operating data from the normal operation obtained in the preceding step; and generating a setting signal upon detecting deviations in the preceding step.

Abstract: A control system for an internal combustion engine is provided which comprises detecting means for detecting a discharge current flowing between electrodes of a spark plug when a high voltage for ignition is applied to the spark plug, judging means for judging whether or not the spark plug is fouled on the basis of the discharge current, and inhibiting means for inhibiting the progress of spark plug fouling when the spark plug is judged fouled. A method carried out by the control system is also provided.

Abstract: In an electronic control for a hybrid vehicle which is driven either by an engine or an electric motor, or both, possible failures in an ignition system and a rotation sensor system are detected during a period in which the engine is rotated by the motor with no fuel supply. Only after no failure is found, the engine is started by supplying fuel and performing ignition. Thus, the fuel supplied to the engine is ignited without fail, and unburned gas release to the atmosphere is surely prevented. Also, good drivability is maintained. In case the invention is applied to a series hybrid vehicle which is driven solely by an electric motor powered by a battery which is charged by an electric generator driven by an engine, the ignition system is diagnosed when the engine is not rotating. After it is determined that there is no failure in the ignition system, the engine is started.