Abstract: During operation of a spark ignition engine, an ignition system produces an output (e.g., breakdown voltage, peak secondary coil current, and spark duration) used to combust a charge (e.g., mixture of air and fuel) in an engine cylinder. Ignition output is important to consider in engines including a second fuel with high ignitability, for example in engines with a fuel reformer system. Example methods, devices and systems are included for adjusting ignition output.

Abstract: A method for operating an engine with a fuel reformer is presented. In one embodiment a first fuel is reformed into a gaseous fuel comprising H, CO, and CH4. The engine is operated by injecting the gaseous fuel and a second fuel to a cylinder of the engine in response to an available amount of gaseous fuel, engine speed and engine load. Further, an engine actuator may be adjusted to vary cylinder charge in response to the available amount of gaseous fuel.

Abstract: An electronic ignition module for vintage automobiles that utilizes existing components and wiring to retain the look and operation of the original system but with superior performance. The ignition module replaces the original roller and contacts of a vintage automobile ignition timer with modern control electronics that actuate the original coils and original spark plugs using the original wiring in the original manor. Electronic ignition operation is user programmable to emulate the original roller/timer performance or provide automatic spark advance similar to modern automobile operation for optimum power and efficiency while freeing the operator from manual adjustment of spark timing. Ignition module programming is accomplished without any external switches, buttons, jumpers or modification to the vintage automobile by simply sensing the presence or absence of ignition coils connected to the system when power is applied.

Abstract: A system for filtering and oxidizing particulate matter produced by a gasoline direct injection engine is disclosed. In one embodiment, engine spark is controlled such that soot held by a particulate filter may be oxidized even during low engine loads.

Abstract: The invention provides an ignition control device for suppressing reverse rotation of the engine during startup process of light duty gasoline engine and a method of suppressing reverse rotation of the engine during startup process of light duty gasoline engine, the ignition control device comprises: a charge coil, a transformer, an electric-spark-generating control circuit, a trigger coil, a position sensing circuit, and a micro-controller. The position sensing circuit is used to shape the positive signal and negative signal of the second alternating current signal induced by the trigger coil while the fly wheel rotates respectively to generate a first position signal and a second position signal and provide the first position signal and the second position signal to the micro-controller.

Abstract: A vehicle control apparatus includes: an accessory that adjusts torque that is output from an internal combustion engine, by giving load to the internal combustion engine; an ignition timing control portion that is provided so as to adjust ignition timing of the internal combustion engine, and that adjusts the torque output from the internal combustion engine by performing a retardation control of the ignition timing; an accessory load adjustment portion that adjusts an accessory load that is the load given from the accessory to the internal combustion engine; and a catalyst that purifies exhaust gas discharged from the internal combustion engine. The ignition timing control portion reduces the retardation of the ignition timing with increase in temperature of the catalyst. The accessory load adjustment portion increases the accessory load with increase in the temperature of the catalyst.

Abstract: An engine mode control system for an internal combustion engine includes a transition control module and an intake cam phaser control module. The transition control module controls a transition from a first engine mode to a second engine mode and determines a desired air mass. The engine is operated at a first air/fuel ratio (AFR) in the first engine mode and at a second AFR in the second engine mode. The desired air mass is based on the second AFR. The intake cam phaser control module adjusts the intake cam phaser based on the desired air mass during the transition.

Abstract: An engine control system comprises a torque request module, an immediate torque control module, an actuation module, and an expected torque control module. The torque request module generates an expected torque request and an immediate torque request. The immediate torque control module controls a spark advance of an engine based on the immediate torque request. The actuation module selectively reduces the expected torque request based on the immediate torque request and a spark capacity. The spark capacity is based on a difference between a first engine torque and a second engine torque, determined at a current airflow. The first engine torque is determined at a first spark advance and the second engine torque is determined at a second spark advance that is less than the first spark advance. The expected torque control module that controls a throttle valve area based on the expected torque request.

Abstract: A method for controlling a radio-frequency plasma generator including a supply circuit with a switch controlled by at least one control pulse train, for applying an intermediate voltage at a control frequency on an output to which is connected a resonator for generating a spark between two electrodes when a high voltage level is applied to the output. The method receives first and second measurement signals respectively representative of the operation of a combustion engine and of the type of spark generated; and real-time adjusts, based on the received measurement signals, at least one parameter selected from at least the intermediate voltage level, the control frequency, and the duration of the control train, to promote branching of the spark generated.

Abstract: A bottom face of a cylinder head (3) defining a combustion chamber (1) is formed substantially in a shape of a spherical shell, and ignition points (21) are arranged in three or more on a concentric circle of 55 to 70% of a diameter of a cylinder block (30) or the vicinity thereof, and combustion is performed with an air excess ratio of the combustion chamber (1) of 1.5 or more.

Abstract: An ECU executes a program including: detecting the engine speed NE and the current KL (S1010, S1020) when the ISC learning control is started (“YES” in S1000); changing the ignition efficiency so that the NE and the output torque are kept unchanged even when the throttle valve opening amount changes (S1030); calculating the target torque by multiplying the ISC target torque by the ignition efficiency (S1040); calculating the target KL based on the target torque, the NE and the MBT (S1050); calculating the throttle valve opening amount based on the target KL (S1060); calculating the target ignition timing based on the NE, the current KL and the target torque (S1070); and controlling an engine using the calculated throttle valve opening amount, ignition timing and fuel injection amount (S1080).

Abstract: A full time lean air fuel mixture running spark ignited air cooled aircraft piston engine. In one embodiment, a drop-in substitution is provided for an equivalent make, model, and engine size, wherein the new, rebuilt, or reconfigured engine provides as much or more horsepower when compared to the original engine, but runs at a lean air fuel ratio condition during normal operating modes, including takeoff, climb, and cruise, thus saving significantly on fuel. In yet another embodiment, a drop-in substitution having a somewhat larger cylinder displacement volume may be provided to attain equivalent or enhanced maximum horsepower while operating at lean air fuel ratios. Enhanced engine life may be anticipated, since cylinder head temperatures (CHTs) may be reduced, compared to engines using rich air fuel ratios for climb and cruise conditions. Aircraft using such engines are also disclosed.

Abstract: An internal combustion engine including: a pulse current generator; at least one electrode including at least one tip; a mechanism controlling the electrical supply to the electrode by the generator; and a combustion chamber in which the tip of the electrode is positioned, the tip being separated from the inner wall of the chamber by a minimum separation distance. The current generator and the electrode are configured such that the power density generated while the electrode is being supplied is less than 105 watts per cubic centimeter, this power density being equal to the electrical supply power of the electrode divided by the minimum separation distance cubed.

Abstract: A method for starting an internal combustion engine with electrically actuated valves, the method comprising during at least a run-up in engine speed of engine starting, adjusting intake valve timing of an electrically actuated valve of a cylinder to provide a desired air amount in said cylinder, based on at least an operating condition of said engine.

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: A control system for controlling the ignition of a plasma-jet spark plug provided in an internal combustion engine senses an operating condition of the internal combustion engine, and determines an ignition mode of the plasma-jet spark plug in accordance with the sensed operating condition. The control system performs an ignition control of breaking down the insulation across a spark discharge gap by applying a first electric power to the plasma-jet spark plug, and producing plasma in the vicinity of the spark discharge gap by applying a second electric power to the spark discharge gap in a state of dielectric breakdown. The control system performs this ignition control according to the ignition mode determined as mentioned above.

Abstract: A method and system for igniting a lean fuel mixture in a main chamber of an internal combustion engine by igniting a rich air-fuel mixture in a pre-combustion chamber which is fuelled using a controlled valve. For a stable and consistent ignition of the main chamber and simultaneous reduction of emission of the internal combustion engines a closed loop control adjusts the fuel amount and the fuelling time for the pre-combustion chamber in order to achieve a light off in an optimal time window and by sufficient ignition energy.

Abstract: In a V-type six-cylinder engine, turbo-superchargers are provided for compressing intake air and feeding the compressed air into combustion chambers, and an ECU is operable to switch the combustion mode from a non-supercharged stoichiometric combustion mode to a supercharged lean combustion mode, depending on the engine operating conditions. When switching from the non-supercharged stoichiometric combustion mode to the supercharged lean combustion mode, the ECU retards the ignition timing, and keeps the retard amount of the ignition timing at a constant value if the increasing actual boost pressure becomes equal to or higher than a pre-set target boost pressure.

Abstract: A control device for an internal combustion engine in which controls can be simplified, and being capable of performing high-performance control by appropriately mediating a plurality of requirements. The device includes an emission control unit, a fuel consumption control unit and an idle stability control unit. Those units output requirements for the internal combustion engine on the basis of their respective aims. An efficiency mediation unit that mediates requirements from those units is provided. Furthermore, an actuator instruction value calculation unit, which determines instruction values for the plurality of actuators installed in the internal combustion engine on the basis of a result of mediation performed by the efficiency mediation unit, is also provided. The requirement is a requirement concerning torque efficiency, which indicates a ratio of a required torque to a reference torque that is obtained when operating points of the plurality of actuators are optimized.

Abstract: A variety of methods and arrangements for improving the fuel efficiency of internal combustion engines are described. Generally, an engine is controlled to operate in a skip fire variable displacement mode. Feedback control is used to dynamically determine the working cycles to be skipped to provide a desired engine output. In some embodiments a substantially optimized amount of air and fuel is delivered to the working chambers during active working cycles so that the fired working chambers can operate at efficiencies close to their optimal efficiency. In some embodiments, the appropriate firing pattern is determined at least in part using predictive adaptive control. By way of example, sigma delta controllers work well for this purpose. In some implementations, the feedback includes feedback indicative of at least one of actual and requested working cycle firings. In some embodiments, the appropriate firings are determined on a firing opportunity by firing opportunity basis.

Abstract: An object to be achieved by the present invention is to achieve ignition timing that is suitable for an environment in which a spark ignition internal combustion engine is used during the period of starting of the internal combustion engine and warm-up thereof just after starting. To achieve this object, according to the present invention, in an ignition control system for an internal combustion engine in which, ignition timing is controlled by feedback in such a way that the engine rotation speed becomes equal to a target rotation speed when the temperature of the internal combustion engine is lower than a prescribed temperature, and retard control for retarding the ignition timing by a predetermined amount from target ignition timing is performed when the temperature of the internal combustion engine is equal to or higher than the prescribed temperature, the aforementioned prescribed temperature is changed according to the altitude of the place where the internal combustion engine is used.

Abstract: An aspect of the invention provides a method for operating a workable homogeneous charge compressed ignition engine in which a compression ignition operation is performed by spark ignition to shorten a load input time and a load cutoff time. In the homogeneous charge compressed ignition engine operating method, a mixture gas is burned by compression ignition in a combustion chamber, and fuel and air are previously mixed to produce the mixture gas. The homogeneous charge compressed ignition engine includes a spark ignition device 53 which performs spark ignition to the mixture gas. A temperature controller 35 substantially keeps an intake air temperature of the mixture gas constant. A spark ignition operation, a spark-assist compression ignition operation in which spark ignition is supplementarily used, and a non-spark compression ignition operation in which the spark ignition is not used are switched according to magnitude of a load.

Abstract: An ignition device performs spark ignition to a fuel mixture in a combustion chamber (13) of an internal combustion engine (100, 101) by using a spark plug (50). The spark plug (50) includes a first electrode (51), a second electrode (52, 11a, 11b, 21), and an insulating member (53, 11c) which is formed from dielectric substance and interposed between the first electrode (51) and the second electrode (52, 11a, 21). By impressing an alternating current between the first electrode (51) and the second electrode (52, 11a, 21), non-equilibrium plasma discharge between the insulating member (53, 11c) and one of the first electrode (51) and the second electrode (52, 11a, 21) is promoted. Igniting the fuel mixture by the non-equilibrium plasma discharge achieves a high ignition performance is achieved with low energy consumption.

Abstract: An engine controller capable of optimizing both the air-fuel ratio and the ignition timing to provide HC-minimized performance under the relevant driving conditions (environmental conditions) in order to minimize the amount of HC emitted from an engine at the time of start-up (before catalyst activation) is provided. The engine controller includes: air-fuel ratio control means for controlling the air-fuel ratio to be within a predetermined range (for example, 14.5 to 16.5) when the engine is operated at a certain driving condition (for example, in a state in which the catalyst is not activated such as the time of starting a cooler, or idling time); and ignition timing correction means for correcting the ignition timing to the retard side when the engine is operated at the certain driving condition and the air-fuel ratio is within the predetermined range.

Abstract: A control device of an internal combustion engine calculates ignition delays in lean combustion and rich combustion, standardizes the ignition delays based on ignition timing, and further standardizes the ignition delays based on injection quantity and injection timing of pilot injection respectively. The control device calculates a present ignition delay by linear interpolation of the standardized ignition delays in the lean combustion and the rich combustion. Moreover, the control device corrects the present ignition delay with the ignition timing and further corrects the present ignition delay with the injection quantity and the injection timing of the pilot injection. The control device calculates a command value of the injection timing by subtracting the corrected present ignition delay from target ignition timing.

Abstract: An internal combustion engine and method of operating such an engine are disclosed. In some embodiments, the engine includes a piston provided within a cylinder, wherein a combustion chamber is defined within the cylinder at least in part by a face of the piston, and an intake valve within the cylinder capable of allowing access to the combustion chamber. The engine further includes a source of compressed air, where the source is external of the cylinder and is coupled to the cylinder by way of the intake valve, and where the piston does not ever operate so as to compress therewithin an amount of uncombusted fuel/air mixture, whereby the engine is capable of operating without a starter. In further embodiments, the piston is rigidly coupled to another, oppositely-orientated second piston, and the two pistons move in unison in response to combustion events to drive hydraulic fluid to a hydraulic motor.

Abstract: A spark-ignition direct-injection internal combustion engine is controlled at low loads through split fuel injections and spark discharges including one injection and spark during a negative valve overlap period and another injection and spark during a compression phase of the engine cycle.

Abstract: A fixed ignition mode in which ignition timing is fixed to a predetermined timing is selected when an engine speed is low. When in the fixed ignition mode, it is determined whether the engine is in a high temperature state or in a non-high temperature state and whether during or after a start-up of the engine. Then, the ignition timing is fixed to a first crank angle, when the engine is in the non-high temperature state, and fixed to a second crank angle retarded from the first crank angle when the engine is in the high temperature state and during the start-up. The ignition timing is fixed to a third crank angle advanced from the second crank angle when, the engine is in the high temperature state and that the start-up has been completed.

Abstract: A method for operating an internal combustion engine, especially an internal combustion engine that is operable, at least in a part-load range, in an operating mode with auto-ignition, in which, at an abrupt change in load and/or at a changeover between an operating mode with auto-ignition and an operating mode without auto-ignition, a parameter of the combustion process correlating with the combustion noise is adapted stepwise over a plurality of combustion cycles from a first parameter value before the abrupt change in load or the changeover to a second parameter value after the abrupt change in load or the changeover, by influencing a combustion position of the combustion process.

Abstract: An engine ignition control apparatus includes a standard ignition map for use in retarding ignition timing when a throttle opening is within a predetermined range, and when an engine speed is within a predetermined region; and an acceleration-time advance angle correction quantity map for performing advance angle correction when the engine speed is within the predetermined region; an engine accelerometer for detecting a rate of change of the engine rotary speed; and an acceleration-time advance angle correction quantity setting unit for correcting an advance angle of the ignition timing. When the engine speed is within the predetermined range, and the rate of change of engine rotary speed is greater than or equal a predetermined rate, the acceleration-time advance angle correction quantity setting unit performs attenuation processing for deriving an advance angle correction quantity; and increases an attenuation quantity of the advance angle quantity for every ignition.

Abstract: An engine ignition control apparatus for controlling ignition of a multi-cylinder, 4-cycle engine includes dual ignition coils for controlling ignition timing of the respective cylinders during engine operation. The engine ignition control apparatus includes a stroke determination unit for determining a stroke based on crank pulses and on an output signal of an intake pressure sensor. The engine ignition control apparatus also includes an ignition map allocation unit for allocating ignition maps to the respective cylinders of two ignition systems, each having a pair of cylinders with a same phase, before the stroke determination. The ignition map allocation unit also allocates ignition maps independently to each of the respective cylinders after the stroke determination. The engine ignition control apparatus also includes an ignition timing calculation unit for calculating ignition timing of the respective ignition coils based on the ignition maps allocated to the respective cylinders.

Abstract: As one example, an engine system for a vehicle is provided, including an internal combustion engine having at least one cylinder; a fuel system configured to provide a fuel to the cylinder; an ignition system including at least a spark plug; a control system configured to vary a level of ignition energy provided to the cylinder via the spark plug in response to a composition of the fuel provided to the cylinder by the fuel system. A method of operating the engine system by varying a level of ignition energy provided to the engine after a start-up is also provided.

Abstract: A control apparatus for an internal combustion engine, includes: a crankshaft; a crank angle detection unit that outputs a crank signal; a generator that rotates in synchronization with the rotation of the crankshaft, and that outputs alternating voltage signals with one-phase; and a control unit, to which the alternating voltage signals are input, that ascertains ignition timings based on the crank signals, performs ignition control so as to spark the internal combustion engine at the ignition timings, determines a polarity of the alternating voltage signal each time the crank signal is detected, ascertains a polarity cycle of the alternating voltage signals based on the determination result of the polarity, and determines that a failure has occurred in the generator when the polarity cycles do not continuously coincide multiple times with the polarity cycles at the time of forward rotation of the crankshaft.

Abstract: The invention deals with a method for operating an internal combustion engine with engine oil as the lubricant and a fuel supply by means of direct injection, wherein an air number (lambda) of a fuel-air mixture supplied to the internal combustion engine is determined. Provision is made in the method according to the invention for the internal combustion engine to be transferred to an operating state with higher fuel consumption, when a low air number (lambda) is detected in driving conditions with a high percentage of fuel ingress from a crankcase ventilation system into the fuel-air mixture. By means of this increase in the fuel requirement, the fuel, which exited the engine oil into the intake air of the internal combustion engine, can be combusted; and an increase in the exhaust gas emissions by means of incompletely combusted fuel, in which typically hydrocarbons and carbon dioxide arise, can be avoided.

Abstract: An ignition device performs spark ignition to a fuel mixture in a combustion chamber (13) of an internal combustion engine (100, 101) by using a spark plug (50). The spark plug (50) comprises a first electrode (51), a second electrode (52, 11a, 11b, 21), and an insulating member (53, 11c) which is formed from dielectric substance and interposed between the first electrode (51) and the second electrode (52, 11a, 21). By impressing an alternating current between the first electrode (51) and the second electrode (52, 11a, 21), non-equilibrium plasma discharge between the insulating member (53, 11e) and one of the first electrode (51) and the second electrode (52, 11a, 21) is promoted. Igniting the fuel mixture by the non-equilibrium plasma discharge achieves a high ignition performance is achieved with low energy consumption.

Abstract: An ignition timing control system for an internal combustion engine, which is capable of reducing the capacity of a memory that stores data used in controlling ignition timing, thereby reducing manufacturing costs. An ignition timing control system that controls ignition timing of an internal combustion engine calculates a maximum torque parameter indicative of a maximum torque that the engine can output when the engine is at the detected rotational speed, according to the detected rotational speed, calculates an output torque parameter indicative of an output torque being output from the engine, calculates a torque ratio as a ratio between the output torque parameter and the maximum torque parameter, and determines the ignition timing according to the engine speed and the torque ratio.

Abstract: The present invention relates to a method of controlling operation of an internal-combustion engine using a single-fuel or a multi-fuel combustion mode with at least one fuel type comprising a high octane number and a low energy density and at least another fuel type comprising a low octane number and a high energy density, a method wherein the energy required for the engine to operate in multi-fuel mode is provided by a combination of two fuel types.

Abstract: An ignition timing value of the internal-combustion engine is calculated by using correction terms including a first correction term that is calculated based on a controlled variable without reflecting a desired value and a second correction term that is calculated based on a difference between the controlled variable and the desired value. The first correction term can be calculated based on the controlled variable with no influence of the desired value. Thus, a sudden change does not occur in the feedback controlled variable even in a situation where the difference between the controlled variable and the desired value changes step-wise. Besides, the first correction term is a proportional term (51) and the second correction term is an integral term (55). The controlled variable is a rotational speed of the internal-combustion engine (NE) that is detected by a detector for detecting the engine rotational speed.

Abstract: An ignition timing circuit is disclosed which provides variable fuel ignition timing as a function of the rotational speed of a small internal combustion engine. A measure of the rotational speed of an engine is generated from the shape of pulses generated by a sensor. A timing delay circuit converts this measure of the rotational engine speed into a fuel ignition trigger signal with a controlled delay relative to the engine's angular position. This trigger signal activates a switching device which in turn delivers energy to the engine's spark plug system. A significant benefit of the disclosed ignition timing circuit is its ability to be enclosed in a package which is size and pin-compatible with standard silicon controlled rectifiers.

Abstract: An ignition timing control system for an internal combustion engine, which is capable of ensuring both stability of control in a steady operating condition of the engine, and an excellent follow-up property of a controlled variable to a target value in a transient operating condition of the engine, even when the controlled variable contains a lot of high-frequency noise components. In the ignition timing control system, a maximum pressure angle-calculating section calculates a maximum pressure angle based on an in-cylinder pressure and a crank angle position. A target angle-calculating section calculates a target angle. A maximum pressure angle controller calculates a maximum pressure angle correction term with a control algorithm to which is applied a sliding mode control algorithm, using a value obtained by performing ?-filtering on a switching function, such that the maximum pressure angle converges to the target angle. The ignition timing is calculated by adding corrected ignition timing to the value.

Abstract: A method is proposed for controlling an internal combustion engine having a crankshaft, in which from the angular pulses of a sensor a pulse time is formed that is a measure for the rotation of the crankshaft of the internal combustion engine per time unit. At a predetermined target angle of the crankshaft, an ignition of a spark plug and an injection of fuel are to take place. A charging of an ignition coil before the ignition and the injection each require a predetermined time duration. The charging of the ignition coil and the injection are each started before the target angle at a start time dependent on the crankshaft, the start times being calculated by taking into account the time duration of the charging and of the portion of the injection before the target angle, and the pulse time, and the pulse counter. The same pulse time is used for the calculation of the start times of the charging of the ignition coil and of the injection.

Abstract: A target value processing unit, includes: an input section to which a target value signal showing a target value of a control process is inputted; a target value shaping unit shaping the target value signal inputted to the input section, into a signal form which is proper for a control treatment of a regulator implementing the control process; and an output section outputting to the regulator a shaped target value signal which is shaped by the target value shaping unit. The target value processing unit realizes the high-level control process without improving the regulator.

Abstract: An electronic control unit for an internal combustion engine having a fuel injection system and an ignition system including: timing determination means (2) for determining timing sequences for injection events of the fuel injection system and ignition events of the ignition system and to provide update timing sequence data (10) to a schedule sequencing means (3) adapted to control at least one driver circuit (4) wherein the at least one driver circuit (4) is adapted to provide drive pulses (11) to the fuel injection system and ignition system; wherein the schedule sequencing means (3) is adapted to select between update sequence data to at least one of an injection of ignition event, such that the update timing sequence data is selected when there is no current injection occurring.

Abstract: An EGR equipped internal combustion engine is controlled to maximize the beneficial effects and minimize the detrimental effects of EGR on engine operation. Specifically, at least one parameter indicative of the O2 concentration in the intake mixture and/or at least one parameter indicative of the H2O concentration in the intake mixture is monitored, and the monitored parameter is relied on to control one or more aspects of engine operation by open loop adjustment of other control strategies and/or by a separate closed loop control strategy. These controls are applicable to virtually any engine, and are particularly beneficial to lean burn engines such as diesel (compression ignition) engines, spark ignited natural gas engines, and dual fuel or other compression ignited natural gas engines. The engine may be equipped with either actively controllable EGR or passive and uncontrolled EGR.

Abstract: A humidity compensation system for an internal combustion engine includes a humidity sensor sensing relative humidity of intake air, a temperature sensor sensing intake air temperature, a pressure sensor sensing intake air pressure and a control circuit computing a specific humidity (SH) value based on the sensor outputs. The control circuit is configured to compute one or more of an adjusted air-to-fuel ratio command as a function of SH and a default air-to-fuel ratio command, an adjusted ignition timing command as a function of SH, engine speed and a default ignition timing command and an adjusted boost pressure command as a function of SH and a default boost pressure command. The control circuit is operable to control any of fueling, ignition timing and boost pressure based on the corresponding adjusted air-to-fuel ratio, ignition timing and boost pressure commands to thereby compensate for humidity effects on engine operation.

Abstract: Systems and methods for controlling an internal combustion engine during and shortly after starting include controlling combustion burn location via ignition timing to improve engine stability while reducing feedgas emissions. Open or closed loop control based on observed or measured mass fraction burned or cumulative released heat allows maintenance of a lean air/fuel ratio charge with significantly retarded ignition timing to reduce catalyst light-off time and temperature and reduce engine feedgas emissions.