Abstract: A method of calibration of at least one fuel injector for a fuel burner in an exhaust gas treatment system for an internal combustion engine is provided. The method is adapted for an exhaust gas system having the fuel burner mounted upstream of a diesel particle filter (DPF). The method of calibration is performed during an idle speed of the combustion engine, this to assure a constant temperature of the burner during the calibration. Hence, the method is started when a first steady tempera tore is registered in the fuel burner, wherein the at least one fuel injector, is operated with a first pulse width. A first temperature of an exhaust gas is registered directly downstream of the fuel burner. After this first temperature is registered, the pulse width, of the fuel injector changed into a second pulse width, which is different from the first pulse width.

Abstract: The invention provides a deterioration diagnostic device for diagnosing a degradation condition of an exhaust gas purifier disposed in an exhaust passage in an engine based on a sensor value of an exhaust gas sensor that is disposed downstream of the purifier. The device includes detecting-signal generating unit for generating a detecting-signal having particular frequency components and multiplying the generated signal to a basic fuel injection amount so as to calculate a fuel injection amount and exhaust gas purifier evaluating for extracting a frequency response corresponding to the detecting-signal from an output of the exhaust gas sensor of the engine, the output being in response to the calculated fuel injection amount, so as to determine a condition of the purifier based on the extracted frequency response.

Abstract: A control system for an internal combustion engine is provided. In the control system, a target intake air amount is calculated according to a target output torque of the engine, and an intake air amount of the engine is controlled according to the target intake air amount. An ignition timing of the engine is controlled.

Abstract: A method and a device for determining, ascertaining and predicting at least one starting torque or starting torque characteristic curve required for starting an internal combustion engine for a vehicle, especially a hybrid vehicle having at least one internal combustion engine and at least one additional motor. The determination and the ascertainment of the starting torque or the starting torque characteristic curve are carried out during the operation of the vehicle. A method for operating at least one motor in a hybrid vehicle is also described.

Abstract: Methods and systems for diagnosing a multiple cylinder engine are provided herein. An exemplary method of diagnosing an internal combustion engine system having a multi-cylinder internal combustion engine is described. In one example, cylinder air-fuel imbalance is determined from the squared value of a difference of two values.

Abstract: An electronic control unit detects an index value of an amount of generated heat of fuel to be combusted in a diesel engine. The electronic control unit also executes the injection of a predetermined amount of the fuel to estimate a cetane number of the fuel and calculates an index value of output torque of the diesel engine generated with that execution. Then, the electronic control unit calculates an estimated value of the cetane number of the fuel based on the index value of the output torque and the index value of the amount of generated heat.

Abstract: An object of this invention is to provide a control apparatus for an internal combustion engine which makes it possible to reliably avoid an abnormal increase in in-cylinder pressure due to pre-ignition. The control apparatus of this invention controls an internal combustion engine including an injector that directly injects fuel into a cylinder. The control apparatus includes pre-ignition detection means that executes an operation to detect pre-ignition until a time of a crank angle ?A, and injection instruction means that, at a time of a crank angle ?B that is before the crank angle ?A, sends to the injector an injection instruction to perform fuel injection that suppresses pre-ignition combustion. Preferably, the control apparatus includes energization stopping means that, when the pre-ignition detection means does not detect pre-ignition until the time of the crank angle ?A, stops energization of the injector that is started by the injection instruction.

Abstract: A system according to the principles of the present disclosure includes a storage estimation module and an air/fuel ratio control module. The storage estimation module estimates a first amount of ammonia stored in a first selective catalytic reduction (SCR) catalyst and estimates a second amount of ammonia stored in a second SCR catalyst. The air/fuel ratio control module controls an air/fuel ratio of an engine based on the first amount, the second amount, and a temperature of a substrate disposed in the second SCR catalyst.

Abstract: Systems and methods are provided for an engine. The system comprises a direct injection engine having a cylinder in which a piston is slidingly supported to form in combination with a cylinder head a combustion chamber; a fuel injector for the cylinder having a catalytic coated tip portion that projects into the combustion chamber; and an electronic controller to control the operation of the engine and operates the engine in a heating mode of operation if heating of the fuel injector tip is requested. Various methods for heating the fuel injector tip are proposed including operating the engine on a reduced number of cylinders and varying one or both of fuel injection timing and quantity of fuel injected and the ignition timing in order to increase the temperature of combustion.

Abstract: In a method for determining the direction of rotation of a drive shaft (13) of an internal combustion engine (1) without using a sensor specifically provided therefor, an operating variable of the internal combustion engine (1) is measured using a sensor in a gas line (40, 16), which connects a combustion chamber (30) of the internal combustion engine (1) to the surrounding area. The operating variable is calculated using a model. A forward direction of rotation of the drive shaft (13) is detected if the difference between the measured value of the operating variable and the model value of the operating variable lies within a specified tolerance range. Otherwise, a reverse direction of rotation of the drive shaft (13) is detected, which is opposite of the forward direction of rotation.

Abstract: To provide a stop control system for an internal combustion engine, which is capable of accurately stopping a piston at a predetermined position while compensating for variation in the stop characteristic of the piston and aging thereof. The stop control system 1 for the engine 3 according the present invention controls a throttle valve 13a toward an open side when an engine speed NE becomes lower than a stop control start rotational speed NEIGOFTH after the engine 3 is stopped (step 42), whereby a final compression stroke rotational speed NEPRSFTGT is controlled to a predetermined reference value NENPFLMTO, to thereby control the stop position of the piston 3d to a predetermined position. Further, the correlation between the stop control start rotational speed NEIGOFTH and the final compression stroke rotational speed NEPRSFTGT is determined (step 5, FIG.

Abstract: An object of the present invention is to prevent hunting of a throttle in a region in which a throttle upstream pressure and a throttle downstream pressure become substantially equal to each other in an internal combustion engine with a supercharger. For this purpose, a control device for an internal combustion engine with a supercharger provided by the present invention processes a signal of a throttle opening which is calculated by using a formula of throttling when a ratio of the throttle upstream pressure and the throttle downstream pressure has a value close to 1, and controls an operation of the throttle with the throttle opening the change speed of which is lessened as a target throttle opening.

Abstract: When executing a Local-learning, an air-fuel ratio detecting time is corrected so that a dispersion of detection values of an air-fuel ratio sensor becomes a maximum value in one cycle of an engine. While executing a cylinder-by-cylinder air-fuel ratio control, a Global-learning is executed. In the Global-learning, the air-fuel ratio detecting time is corrected based on a relationship between a variation in estimated air fuel ratio of each cylinder and a variation in fuel quantity correction value of each cylinder. In the Global-learning, a computer computes a correlation coefficient between the variation in estimated air-fuel ratio and the variation in fuel quantity correction value of the cylinder for each case where the cylinder assumed to correspond to the estimated air fuel ratio is hypothetically varied in multiple ways. Then, the air-fuel ratio detecting time is corrected so that this correlation coefficient becomes a maximum value.

Abstract: A device for separating fuel components comprising a separating membrane for separating high-octane fuel components from un-separated fuel and a heat exchanger between first liquid passing through the heat exchanger and second liquid passing through the heat exchanger, is provided. The first liquid is un-separated fuel passing through the heat exchanger before being supplied to the separating membrane. The second liquid is low-octane fuel remaining when the high-octane fuel components are separated from the un-separated fuel, passing through the heat exchanger after changing to an almost liquid phase.

Abstract: A method for determining at least one rail pressure/closing current value pair for a pressure control valve of a common rail injection system of an internal combustion engine includes the following steps: operating the common rail injection system in an MU control mode; reducing the control current for the pressure control valve; detecting the pressure curve over time in the common rail and determining the rail pressure; determining the closing current based on the detected pressure curve; and associating the determined rail pressure and the determined closing current with a rail pressure/closing current value pair.

Abstract: A fuel injection amount control system acquires an air-fuel ratio imbalance index value that increases as the degree of ununiformity in the air-fuel ratio among cylinders increases, based on an output value of an upstream air-fuel ratio sensor, and acquires an imbalance index learned value by performing a first-order lag filtering operation for removing noise, on the air-fuel ratio imbalance index value. Also, the fuel injection amount is increased based on the imbalance index learned value. In the filtering operation, the time constant of the filter is set to a smaller value when a magnitude of a difference between the current value and the last value of the air-fuel ratio imbalance index value is equal to or larger than a threshold value.

Abstract: A control chip for providing the basic functionality of a control unit includes a voltage supply having at least two, in particular three, output voltages; at least two, in particular three, sensor power supplies, in particular having 5-V and/or 3.3-V output voltage; at least one driver for bidirectional interfaces; a CAN driver; a follower control; a main relay output stage having a diagnostic function; at least one bidirectional serial interface for controlling the output stages and for communicating with a microcontroller; at least six power output stages, in particular having rated currents of 0.6 A to 3 A; at least one low-level signal output, in particular having a rated current of 50 mA, and four ignition drivers.

Abstract: A system and method for controlling the viscosity of liquid fuel delivered from a fuel tank to the fuel injectors of an internal combustion engine. A viscosity sensor is placed in the fuel line, or in a bypass fuel line, in close proximity downstream the fuel injectors. A heat exchanger is placed on the fuel line downstream the sensor. The sensor is a rotating cylinder having a nominal rotation velocity, and is configured to rotate such that the nominal rotation velocity increases or decreases in response to fuel viscosity. The sensor delivers a measurement signal to a control unit, which performs a closed loop algorithm to adjust the heat provided by the heat exchanger until the measured rotation matches a target rotation.

Abstract: A method of operating a vehicle including an engine is provided. The engine may include at least one cylinder, a boosting device to boost intake air to the at least one cylinder, a fuel tank, a fuel vapor canister to store fuel vapors vented from the fuel tank, and an emission control device to treat exhaust gas from the engine. The boosting device includes a compressor at least partially driven by an electric motor. The method includes during an engine cold start condition, operating the electric motor of the boost device to boost intake air, directing the boosted intake air through the fuel vapor canister to release a fuel vapor stored in the fuel vapor canister, directing the fuel vapor from the fuel vapor canister to the engine, and performing combustion in the at least one cylinder using the fuel vapor during the engine starting.

Abstract: A control system includes a starter control module, a mode setting module, a throttle control module, and a fuel control module. The starter control module initiates cranking of a spark ignition direct injection (SIDI) engine in response to user actuation of an ignition switch. The mode setting module sets a mode of operation to a coldstart mode when an engine coolant temperature is less than a predetermined temperature during the cranking. The throttle control module allows a throttle valve to be biased to a predetermined open position when the SIDI engine is off and, in response to the setting of the mode to the coldstart mode, selectively closes the throttle valve relative to the predetermined open position during the cranking. The fuel control module, in response to the setting of the mode to the coldstart mode, disables direct injection of fuel for a first combustion event during the cranking.

Abstract: A method for determining the quantity of outgassing of a fuel from a lubricant located in an intake section housing of an internal combustion engine may include (a) setting a first coil current through the housing, (b) measuring a first output value of a lambda controller, (c) setting a second coil current through the housing, the second coil current having a different current strength than the first coil current, (d) measuring a second output value of the lambda controller and (e) determining the quantity of outgassing of the fuel based on the measured first and second output values. In addition, a method for adapting a lambda value for a fuel/air mixture to be burnt in an internal combustion engine during a lower load range may include the above-mentioned method of determining the quantity of outgassing of a fuel.

Abstract: A method for operating a compression-ignition engine includes controlling an engine fueling, a compressor boost pressure, and an EGR content in a cylinder charge to maintain engine operation in response to a biodiesel blend ratio of a biodiesel fuel blend.

Abstract: In an operating method for an internal combustion engine with direct fuel injection including a plurality of combustion chambers, in particular a direct-injection gasoline engine for a motor vehicle, wherein the operating method comprises low-NOx combustion (NAV) and uses a plurality of partial operating modes, wherein, in a NAV partial operating mode, water is injected into the respective combustion chamber, and, during said NAV partial operating mode, at an ignition point (ZZP), a largely homogeneous, lean fuel/exhaust gas/air mixture having a combustion air ratio of ??1 is spark ignited by means of an ignition device so as to initiate flame front combustion (FFV) with a transition to a controlled auto-ignition (RZV). The injection of water permits the NAV partial operating mode to be stably implemented even at high engine loads and speeds.

Abstract: A method for operating an internal combustion engine, in which a setpoint torque to be output by the internal combustion engine is restricted to a specifiable torque, in particular in response to an error in the control of the internal combustion engine. An engine speed of the internal combustion engine is determined as a function of at least one performance quantity of the internal combustion engine, and the specifiable torque is modified as a function of the determined engine speed.

Abstract: A connection assembly for securing electrical components used with power equipment comprises a housing and connector cover forming an upper arrangement of the connection assembly. The housing and connector cover form a cavity therebetween for supporting electronics disposed within the cavity. The connection assembly also comprises a lower arrangement used to secure the connection assembly to a surface of a power equipment device and a hinge assembly that forms a rotational connection between the upper arrangement and the lower arrangement.

Abstract: This disclosure provides a thermal management system and method that can recommend operational behavior to an operator of an engine system to optimize fuel economy over a period of time in which a components of the engine system is in a warm up and/or regeneration state. In one representative embodiment, the expected temperature change of the engine component at a later time is determined based on inefficient operation of the engine, such as a transmission down shift resulting in higher engine speed and lower engine torque, and the expected temperature change of the engine component resulting from operating the engine under current conditions or expected conditions at that later time is determined. A determination is made as to whether the inefficient engine operation is the optimal operation in view of fuel economy and a recommendation is generated for the operator based if optimal operation is determined.

Abstract: An oxygen sensor system for a vehicle includes a pump control module, a correction module, and a fuel control module. While fueling of an engine is cut off, the pump control module selectively turns ON an air pump that pumps ambient air into an exhaust system of the vehicle upstream of a universal exhaust gas oxygen (UEGO) sensor and a catalyst. The correction module receives an output of the UEGO sensor, selectively determines a correction for the output of the UEGO sensor when the air pump is ON and the fuel is cut off, and adjusts the output of the UEGO sensor based on the correction to produce a corrected output. The fuel control module, during fueling of the engine, selectively controls the fueling based on the corrected output.

Abstract: An electronic control unit (“ECU”) limiter is disclosed. The ECU can include a vehicle-mounted component configured to measure and interact with components of the vehicle such as the engine, the transmission, etc, and a remote component configured to communicate with the vehicle-mounted component and vice versa. The vehicle-mounted component can be programmed to permit the vehicle to operate substantially without limitation until a certain parameter threshold is met, such as the engine usage reaching a certain predetermined quantity. The vehicle-mounted component can limit the engine in a variety of ways when the parameter threshold is met. The remote component can receive information from the vehicle-mounted component regarding the monitored parameters and the limitations caused by the vehicle-mounted component.

Abstract: A diesel engine 100 is provided with a common rail type fuel injection device. A controller 14 controls a common rail pressure and an engine control parameter other than the common rail pressure, respectively, to target values that are determined on the basis of the engine load. The controller 14 corrects the engine control parameter other than the common rail pressure when the common rail pressure does not coincide with the target common rail pressure in a transient state of the diesel engine, thereby preventing an air-fuel ratio in the combustion region from becoming lean.

Abstract: A method for controlling differences in exhaust gas residual amount for a two cylinder bank engine having at least one turbocharger is presented. In one example, the description includes a method for adjusting valve timing to reduce cylinder exhaust gas residual variation.

Abstract: An engine controlling apparatus includes an engine speed detection unit that detects an engine speed, and an acceleration operation amount detection unit that detects an acceleration operation amount inputted to an acceleration pedal. The apparatus includes a first calculation unit that calculates an acceleration demand torque based on the engine speed and the acceleration operation amount, a second calculation unit that calculates an external demand torque demanded from an external controlling system, and a third calculation unit that calculates a first target torque and a second target torque based on the acceleration demand torque and the external demand torque. The apparatus includes a fourth calculation unit that calculates a maximum torque which can be generated by the engine at an actual charging efficiency, and a control unit that controls an ignition timing of the engine based on the actual torque and the first target torque.

Abstract: A control apparatus for a supercharged internal combustion engine, which can achieve a target torque accurately even if the target torque contains a high-frequency vibration component. The control apparatus determines a target air quantity and a target boost pressure from a target torque, operates an actuator for air quantity control according to the target air quantity, and operates an actuator for boost pressure control according to the target boost pressure. The target torque is formed to contain a low-frequency torque component that is set at all times based on a torque requirement from a driver and a high-frequency torque component that is set as necessary for a specific type of vehicle control. When the target torque contains only the low-frequency torque component, the target boost pressure is formed using a pressure component corresponding to the low-frequency torque.

Abstract: An actual maximum fuel injection rate is computed based on a falling waveform and a rising waveform of the fuel pressure. The falling waveform represents the fuel pressure detected by a fuel sensor during a period in which the fuel pressure increases due to a fuel injection rate decrease. The rising waveform represents the fuel pressure detected by the fuel sensor during a period in which the fuel pressure decreases due to a fuel injection rate increase. The falling waveform and the rising waveform are modeled by modeling functions. A reference pressure is computed based on pressure during a specified time period before the falling waveform is generated. An intersection pressure is computed, at which the straight lines expressed by the modeling functions intersect to each other. The maximum fuel injection rate is computed based on a fuel pressure drop from the reference pressure to the intersection pressure.

Abstract: An alcohol concentration sensor detects an alcohol concentration in fuel that is supplied to an internal combustion engine. A fuel injection quantity is controlled in accordance with a detection value of the alcohol concentration that is detected by the alcohol concentration sensor. When a temperature of the fuel, which is detected by a fuel temperature sensor or estimated from intake air temperature etc., is equal to or lower than a predetermined limit temperature, the detection value of the alcohol concentration, which is detected by the alcohol concentration sensor, is memorized as a memorized value of the alcohol concentration. When the temperature of the fuel is higher than the predetermined limit temperature, the fuel injection quantity is controlled by using the memorized value of the alcohol concentration instead of using the detection value, which is currently detected by the alcohol concentration sensor.

Abstract: A method for controlling combustion in a multi-cylinder engine includes injecting fuel into at least one cylinder of the multi-cylinder engine and, for each cylinder, separately controlling at least one fuel injection parameter to produce a desired exhaust composition for that cylinder. A multi-cylinder engine is also disclosed.

Abstract: A common rail fuel system diagnostic algorithm is executed by an engine control and real time to detect and identify a faulty fuel system component. Rail pressure data is processed through a digital resonating filter having a resonance frequency corresponding to a fault signature. A peak magnitude and phase of the output from the digital resonating filter reveals a degradation level of a fuel injector, and a phase of the output identifies which fuel injector is faulted.

Abstract: A speed change system for work vehicle having a continuously variable transmission device selects a first change gear ratio which is set larger than a smallest change gear ratio, when an engine rotational speed is a first set rotational speed which is set equal or close to an idling rotational speed of an engine; retains the change gear ratio of the continuously variable transmission device at the smallest change gear ratio, when the engine rotational speed is equal to or above a second set rotational speed set on a high-speed side relative to the first set rotational speed; and makes the change gear ratio of the continuously variable transmission device larger between the first change gear ratio and the smallest change gear ratio, as the engine rotational speed at that moment becomes lower, when the engine rotational speed is between the first and second set rotational speeds.

Abstract: A system, a controller, and a method for controlling a fuel injector during start-up of a fuel injected internal combustion engine. The fuel injector has a heater element configured to heat liquid fuel, such as gasoline, ethanol, gasoline/alcohol blends, diesel, or JP-8 within the fuel injector and indicate heater temperature. The controller is configured to estimate a fuel temperature based on the heater temperature, determine a crankshaft angle at which to initiate an injection event based on the fuel temperature, and initiate the injection event at the determined crankshaft angle. The controller is further configured to determine injection duration based on the fuel temperature and operate the fuel injector according to the determined injection duration. The controller may delay the injection event until the fuel temperature reaches a fuel temperature threshold. The injection event may be a priming injection event, cranking injection event, or running injection event.

Abstract: An inter-cylinder air-fuel ratio imbalance determination apparatus (determination apparatus) according to the present invention obtains, as an “EGR supplying state imbalance determination parameter”, a value corresponding to a differential value d(abyfs)dt of a detected air-fuel ratio abyfs represented by an output value of an air-fuel ratio sensor when an EGR gas is being supplied, and obtains, as an “EGR stop state imbalance determination parameter”, a value corresponding to a differential value d(abyfs)dt when an EGR gas supply is being stopped. The determination apparatus obtains an “EGR-causing imbalance determination parameter Pegr” by subtracting the EGR stop state imbalance determination parameter Poff from the EGR supplying state imbalance determination parameter Pon, and determines that an inter-cylinder air-fuel ratio imbalance state has occurred due to the supply of the EGR gas when the parameter Pegr is larger than a threshold Pegrth.

Abstract: A two-stroke engine (1) has a cylinder (2) defining a combustion chamber (3) delimited by a piston (5). The piston (5) drives a crankshaft (7) which is rotatably journalled in a crankcase (4). The crankcase (4) is connected to the combustion chamber (3) via a transfer channel (17) at at least one position of the piston. The two-stroke engine has an inlet (11) into the crankcase (4) and an outlet (19) from the combustion chamber. There is an arrangement to supply fuel, a control, and a device to determine the crankcase pressure (pKGH). A method to operate the two-stroke engine (1) includes determining the crankcase pressure (pKGH) during every engine cycle. The fluctuation in the crankcase pressure (pKGH) is determined and the fluctuation is compared to a limit value (?plimit) to determine whether a combustion occurs during every engine cycle. In this way, a determination can be reliably made as to whether the two-stroke engine is running in a four-stroke mode.

Abstract: An object of the present invention is to provide a gas turbine control device which is capable of performing correction on the basis of a fuel composition of fuel gas to be supplied to a gas turbine, and is capable of changing an amount of correction in response to variation with time of the gas turbine. To attain this, a frequency analyzing unit 25 performs a frequency analysis of combustion oscillation of a combustor and splits a result of the analysis into respective frequency bands. Then, a state grasping unit 22 checks an operating state of the gas turbine on the basis of the result of the analysis of the combustion oscillation and process value of the gas turbine, and corrects the checked operating state on the basis of a fuel composition or a heat capacity of fuel gas measured by a fuel characteristic measuring unit 200. A countermeasure determining unit 23 conducts a countermeasure for controlling an operating action of the gas turbine on the basis of the operating state thus checked.

Abstract: Methods and systems are provided for operating an engine having a plurality of notch settings. One example method comprises, during a first notch setting, adjusting engine injection timing in a first proportion to an increasing temperature, and during a second notch setting higher than the first notch setting, adjusting engine injection timing in a second proportion to the increasing temperature, the second proportion lower than the first proportion.

Abstract: A control device is applied to an internal combustion engine capable of using CNG and gasoline by switching therebetween, and the CNG and the gasoline are associated, as fuel for use, with one and the other of two driving areas respectively, the driving areas being different from each other. The control device exceptionally switches the fuel for use from gasoline to CNG and implements an air-fuel ratio imbalance inspection (S6, S7), when the air-fuel ratio imbalance inspection is required for a CNG mode using CNG (S1), the engine is driving in a driving area (AR2) correlated to gasoline as fuel for use (S2), and gasoline mode using gasoline as fuel for use is ongoing (S3).

Abstract: An engine control system includes an air control module, a spark control module, and a reserves module. The air control module controls a throttle valve of an engine based on an adjusted predicted torque request. The spark control module controls spark timing of the engine based on an adjusted immediate torque request. The reserves module determines an arbitrated reserve based on a maximum one of a minimum reserve and an additive reserve sum. The reserves module also generates the adjusted predicted torque request based on a sum of an arbitrated predicted torque request and a requested reserve, wherein the requested reserve is based on the arbitrated reserve.

Abstract: The invention is a method of controlling the combustion of a diesel engine comprising determining setpoint values for physical parameters linked with the intake of gaseous oxidizer in the combustion chamber, and a setpoint value ?injref for the crank angle at which fuel has to be injected into the combustion chamber. While the engine control system controls actuators in such a way that the values of the physical parameters are equal to the setpoint values, setpoint value ?injref is corrected before the physical parameters reach their setpoint values, by accounting for the differences between the real values of the physical parameters and the setpoint values of these parameters. Finally, the engine control system controls fuel injection into the combustion chamber when the crank angle is equal to this corrected setpoint value ?injref in order to keep combustion optimal.

Abstract: Methods and systems for monitoring an internal combustion engine are disclosed. In one example, output of a temperature sensor is converted into a fuel pressure variable to determine if fuel system components are operating as desired and cylinder air charge may be limited if degradation is determined. The methods and systems may reduce fuel system cost while also providing redundant system data.

Abstract: A method of estimating the individual fuel air ratio richness of an individual cylinder in an engine by utilizing a single oxygen sensor at the confluence of a plurality of exhaust runners. The method provides for the use of a wide range or switching oxygen sensor at the confluence of a plurality of exhaust runners.

Abstract: Methods and systems are provided for improving fuel usage while addressing knock by adjusting the use of spark retard and direct injection of a knock control fluid based on engine operating conditions and the composition of the injected fluid. One or more engine parameters, such as EGR, VCT, boost, throttle position, and CMCV, are coordinated with the direct injection to reduce torque and EGR transients.

Abstract: Provided is a control apparatus, which can successfully suppress that deterioration of combustion is caused in response to inflow of a large amount of blow-by gas to cylinders at the time of a valve return from a valve stop state in an internal combustion engine including a positive crankcase ventilation system and a variable valve operating mechanism that is capable of stopping at least one valve of an intake valve and exhaust valve in a closed state. A valve stop control is performed which stops the intake valve and exhaust valve in a closed state when a fuel cut of the internal combustion engine is executed. A deviation amount ?A/F between a predetermined target air fuel ratio and an actual air fuel ratio detected by an A/F sensor at the time of a valve return is obtained. A correction is performed to decrease a fuel injection amount by a fuel amount equivalent to the deviation amount ?A/F at the time of the subsequent valve returns.

Abstract: Provided is an internal combustion engine system controller, including a sub-feedback learning section, a state determining section, and a learning update-speed setting section. The state determining section determines, to which of at least three states including: (a) a stable state in which a fluctuating state of a sub-feedback learning value is stable; (b) an unstable state in which the fluctuating state greatly fluctuates; and (c) an intermediate state between the stable state and the instable state (may be referred to as sub-stable state), the fluctuating state corresponds. The learning update-speed setting section sets an update speed of the sub-feedback learning value in accordance with the result of determination by the state determining section. Further, the learning update-speed setting section suppresses the occurrence of hunting of the sub-feedback learning value.