Abstract: An apparatus to control an internal combustion engine includes a cylinder operation controller configured to switch a cylinder operation between an all-cylinder operation and a cylinder deactivation operation. A deactivation time parameter integrating device is configured to integrate a deactivation time parameter indicating a deactivation time of the part of the plurality of cylinders to calculate an integrated deactivation time parameter. An inhibiting device is configured to inhibit the cylinder deactivation operation if the integrated deactivation time parameter calculated by the deactivation time parameter integrating device is larger than or equal to a reference value. The deactivation time parameter integrating device holds the integrated deactivation time parameter as an initial value after an operation of the internal combustion engine is stopped.

Abstract: A stop control system for an internal combustion engine, which is capable of accurately stopping a piston at a predetermined position during stoppage of the engine while preventing occurrence of untoward noise and vibration. After stopping the engine 3, the stop control system 1 for the engine 3 according to the present invention executes a first stage control (step 34) in which a throttle valve 13a is controlled to a first stage control target opening degree ICMDOFPRE smaller than a second predetermined opening degree ICMDOF2, in order to stop the piston at the predetermined position, before executing a second stage control (step 42) in which the throttle valve 13a is controlled to the second predetermined opening degree ICMDOF2.

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: 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: A stop control system for an internal combustion engine, which is capable of accurately stopping a piston at a predetermined position during stoppage of the engine while preventing occurrence of untoward noise and vibration. After stopping the engine 3, the stop control system 1 for the engine 3 according to the present invention executes a first stage control (step 34) in which a throttle valve 13a is controlled to a first stage control target opening degree ICMDOFPRE smaller than a second predetermined opening degree ICMDOF2, in order to stop the piston at the predetermined position, before executing a second stage control (step 42) in which the throttle valve 13a is controlled to the second predetermined opening degree ICMDOF2.

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 apparatus to control an internal combustion engine includes a cylinder operation controller configured to switch a cylinder operation between an all-cylinder operation and a cylinder deactivation operation. A deactivation time parameter integrating device is configured to integrate a deactivation time parameter indicating a deactivation time of the part of the plurality of cylinders to calculate an integrated deactivation time parameter. An inhibiting device is configured to inhibit the cylinder deactivation operation if the integrated deactivation time parameter calculated by the deactivation time parameter integrating device is larger than or equal to a reference value. The deactivation time parameter integrating device holds the integrated deactivation time parameter as an initial value after an operation of the internal combustion engine is stopped.

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: An ignition timing control system and method, and an engine control unit for an internal combustion engine, which are capable of setting optimum timing for execution of retardation of ignition timing when a vehicle on which the engine is installed is accelerated, thereby effectively reducing longitudinal vibrations of the vehicle, and maintaining acceleration performance. An acceleration demand-detecting module detects a demand of acceleration of the engine. A rotational speed-detecting module detects a rotational speed of the engine. A rotational variation amount-calculating module calculates a variation amount of the rotational speed of the engine. A rotational variation amount differential value-calculating module calculates a differential value of the variation amount of the rotational speed of the engine. A retard amount-calculating module calculates a retard amount for retarding the ignition timing.

Abstract: There is provided an ignition timing control system and method and an engine control unit for an internal combustion engine, which are capable of setting optimum timing for execution of retardation of ignition timing when a vehicle on which the engines is installed is accelerated, thereby effectively reducing longitudinal vibrations of the vehicle, which might be caused by torque fluctuations, and maintaining acceleration performance. An acceleration demand-detecting module detects a demand of acceleration of the engine. A rotational speed-detecting module detects a rotational speed of the engine. A rotational variation amount-calculating module calculates a variation amount of the rotational speed of the engine, based on the detected rotational speed of the engine. A rotational variation amount differential value-calculating module calculates a differential value of the variation amount of the rotational speed of the engine, based on the calculated variation amount of the rotational speed of the engine.

Abstract: A fuel supply control system for an internal combustion engine has an exhaust gas-purifying device arranged in the exhaust system of the engine. When a predetermined high load condition of the engine is detected, an amount of fuel supplied to the engine is increased. Temperature values indicative of the temperature of the exhaust gas-purifying device are stored and a stored temperature value is read out according to operating conditions of the engine. A correction coefficient for correcting the read-out temperature value is determined, and the temperature of the exhaust gas-purifying device is estimated based on the read-out temperature value and the determined correction coefficient. When the predetermined high load condition is detected and at the same time the estimated temperature is higher than a predetermined temperature value, the amount of fuel supplied to the engine is actually increased.

Abstract: An evaporative fuel-processing system for an internal combustion engine includes a canister, a charging passage extending between the canister and a fuel tank, a purging passage extending between the canister and the intake system of the engine, an open-to-atmosphere passage for relieving the interior of the canister to the atmosphere, a charge control valve for opening and closing the charging passage, a purge control valve for opening and closing the purging passage, a vent shut valve for opening and closing the open-to-atmosphere passage, and a pressure sensor for detecting pressure within the charging passage. When the engine is in a predetermined operating condition, the interior of the fuel tank is negatively pressurized into a predetermined negatively pressurized state by opening the purge control valve and the charge control valve and closing the vent shut valve.

Abstract: There is provided a control system for an internal combustion engine. An amount of variation in the rotational speed of the engine is detected. A rotational speed variation reference value is calculated based on an averaged value of the detected amount of variation in the rotational speed of the engine. The detected amount of variation in the rotational speed of the engine is compared with the rotational speed variation reference value. The amount of fuel to be supplied to the engine is corrected based on results of the comparison.

Abstract: An evaporative emission control system for an internal combustion engine has a purge control valve arranged in a purging passage connecting between a canister and an intake passage of the engine. The evaporative emission control system has a self-diagnosis function of determining whether the evaporative fuel emission control system is normal or abnormal from a change in a value of a parameter measured based on an output from an exhaust gas component concentration sensor arranged in an exhaust passage of the engine, which change is detected when the opening of the purge control value is changed, and a variation in pressure within the intake passage at a location downstream of a throttle valve arranged therein when the opening of the purge control valve is changed.

Abstract: An improved evaporative fuel-purging control system for controlling a purging flow rate which is controlled by a solenoid purge control valve regulated with a pulse waveform signal. As for the characteristic of the purge control valve, differing periods of the signal differentiates the control valve linearity of purging flow rate with respect to the signal duty ratio. To improve the linearity, the pulse waveform signal period which creates the substantial linearity is selected among preset periods periods according to the preset duty ratio which works as a threshold value.

Abstract: Ignition timing control system for internal combustion engines. The system comprises a means for detecting operating parameters of the engine such as engine speed, engine load, the presence of knock, a means for determining a basic ignition timing on the basis of the engine speed and load, a means for determining a first group of retard amounts based on the detected operating parameters to prevent knock from occurring, and a means for determining a second group of retard amounts based on the detected operating parameters to intentionally reduce output torque of the engine. The first retard amount group is compared with the second one the basic ignition timing is corrected by the selected value. With the arrangement, the retard amount is limited to the minimum required even when engine operating conditions producing knock and requiring engine output reduction are present at the same time.