Abstract: In order to provide an intake flow rate detecting apparatus of an internal combustion engine which accurately compensates for an air flow meter detection error due to intake pulsation so as to make it possible to detect an intake flow rate more accurately, regardless of the of type of flow rate control mechanism, an intake flow rate detecting apparatus according to one embodiment of the invention includes a throttle valve which is provided in an intake passage and which adjusts a rate of the air that is taken into a combustion chamber of an internal combustion engine, at least one flow rate control mechanisms which are provided between the throttle valve and the combustion chamber and which control an air flow rate between the throttle valve and the combustion chamber, and a flow rate sensor which is provided upstream of the throttle valve in the intake passage and which detects a flow rate of air flowing through the intake passage.

Abstract: An intake air-flow rate detecting apparatus of an internal combustion engine according to the present invention has a thermal air-flow sensor for detecting an intake air-flow rate of the internal combustion engine, and a response lag compensator for compensating for a response lag of the air-flow sensor, using a first-order lag element concerning a heat release amount in the air-flow sensor. Since the response lag process is carried out on the dimension of the heat release amount, the response lag of the air-flow sensor can be compensated for with accuracy and the response lag of the thermal air-flow sensor can be compensated for with high accuracy.

Abstract: Flow amount calculation controller controls a certain subject based on a flow amount of fluid, passing through a variable throttle portion provided in an air passage, calculated from an upstream pressure Pu, an upstream density &rgr;u, a downstream pressure Pd, an opening area Ad and a specific heat ratio k by the following formula.

Abstract: An intake pressure computing apparatus and a method for the same compute an intake pipe pressure P0 based on a sum of a throttle passing air amount QA0 calculated based on at least a throttle opening and a flow of purge air that flows into an intake pipe through a purge passage, or a purge flow rate QP, and compute an intake pipe pressure P3 using an intake air amount QA based on an output from an air flow meter. An intake air amount computing apparatus and a method for the same compute an amount of air drawn into an engine, or an intake air amount, based on the intake pipe pressure P0 and the intake pipe pressure P3.

Abstract: Flow amount calculation controller controls a certain subject based on a flow amount of fluid, passing through a variable throttle portion provided in an air passage, calculated from an upstream pressure Pu, an upstream density &rgr;u, a downstream pressure Pd, an opening area Ad and a specific heat ratio k by the following formula.

Abstract: An intake air-flow rate detecting apparatus of an internal combustion engine according to the present invention has a thermal air-flow sensor for detecting an intake air-flow rate of the internal combustion engine, and a response lag compensator for compensating for a response lag of the air-flow sensor, using a first-order lag element concerning a heat release amount in the air-flow sensor. Since the response lag process is carried out on the dimension of the heat release amount, the response lag of the air-flow sensor can be compensated for with accuracy and the response lag of the thermal air-flow sensor can be compensated for with high accuracy.

Abstract: A control apparatus of an internal combustion engine is able to effectively suppress vibration occurring upon acceleration of a motor vehicle due to an increase in the torque generated by the engine. The apparatus controls the ignition timing in accordance with variations in the acceleration of the motor vehicle, so as to variably control the torque generated by the engine. Upon the start of variable torque control, a controller controls the opening amount of the throttle valve to be larger than the opening amount originally determined depending upon the current operating conditions of the engine. As a result, the generated torque is allowed to be larger than the normally generated torque during variable torque control, and vibration upon acceleration can be effectively suppressed.

Abstract: In a throttle control apparatus of an internal combustion engine, when the driver operates an accelerator so as to cause a motor vehicle to proceed to a steady-state running mode, a target throttle opening amount is no longer controlled to a throttle opening amount that depends upon an operated amount of the accelerator. Instead, the throttle opening amount is controlled to a value that provides a steady-state required torque. In this manner, the vehicle is immediately brought into a desired steady-state running mode, without requiring the driver to repeatedly operate the accelerator since the accelerator operation is not directly reflected by the throttle opening amount. Thus, the driver need not frequently repeat accelerator operations when the vehicle enters a steady-state running mode, thus assuring improved driveability.

Abstract: An air-fuel ratio control apparatus of an internal combustion engine is provided which enables highly accurate calibration of an air-fuel feedback correction value to be completed in a short time, thus avoiding adverse influences on the emissions. The engine load is fixed when the air-fuel ratio or purge concentration is calibrated from the behavior of the air-fuel ratio feedback correction value. Thus, no change is observed in the engine load even if the driver operates the accelerator pedal to adjust the accelerator pedal position so as to change the required torque, and the air-fuel ratio of the air-fuel mixture is stabilized. Accordingly, air-fuel ratio calibration or purge concentration calibration can be promptly accomplished with high accuracy. Furthermore, while the engine load is being adjusted, the output torque is controlled in accordance with the required torque by adjusting the ignition timing.

Abstract: An air-fuel ratio control apparatus performs an intake air-increasing process based on a region of an air-fuel ratio feedback adjustment coefficient FAF in which the adjustment coefficient decreases the fuel concentration in an air-fuel mixture. The apparatus calculates a fuel injection valve open duration TAU by using a newly calculated air-fuel ratio feedback adjustment coefficient FAFx, instead of using an adjustment coefficient FAF. An air-fuel ratio-increasing feedback adjustment coefficient FVLV in the adjustment coefficient FAFx has a value that cancels an increase in the amount of intake air. Therefore, the fuel injection amount is increased only when the fuel concentration in the mixture is an intake air-increasing process. Hence, torque difference between fuel concentration-increasing and concentration-decreasing control becomes smaller.

Abstract: An apparatus for controlling air-fuel ratio in an engine provided with a fuel vapor purging system. The purging system sends the fuel vapor in a fuel tank to an intake passage. The actual air-fuel ratio is computed from the oxygen concentration of the exhaust gas. An electronic control unit (ECU) adjusts the amount of fuel injected from an injector. The ECU sets a feedback correction coefficient FAF to correct the difference between the actual air-fuel ratio and a predetermined target air-fuel ratio. The feedback correction coefficient FAF is feedback controlled. The ECU further considers fluctuations of the air-fuel ratio caused by the purging system in accordance with the operating state and operating history of the engine.

Abstract: The engine of the present invention has a plurality of cylinders that are divided into a first group and a second group. An air flow meter for detecting an amount of air supplied to the engine is provided downstream of an air cleaner in an intake system. A crank angle sensor for detecting a rotational speed of the engine is provided adjacent to a crank shaft. The amount of air distributed to the first group and the amount of air distributed to the second group are calculated based on the detected amount of air and the detected rotational speed of the engine. The amount of fuel injected into the first group and the amount of fuel injected into the second group are corrected according to the calculated amounts of air distributed to the first and second groups.