Abstract: The intake flow velocity near the jet of a fuel injection valve is obtained on the basis of the engine rotational speed, engine intake air quantity and intake valve opening area. A crank angle position for maximum intake flow velocity is set as the timing for completion of fuel injection by the fuel injection valve. As a result, fuel injection can be reliably completed at a timing giving good fuel atomization characteristics.

Abstract: A water temperature base increase correction amount for an internal combustion engine is reducingly corrected while maintaining the level of the surge-torque below a fixed level. A time constant for updating of the reduction correction is set based on a delay time from supply of fuel until generation of torque from combustion of the fuel. In this way responsiveness to the fuel reduction correction can be maintained, enabling improvement in fuel costs and exhaust emissions. Furthermore, the detection of the surge-torque necessary for example, for the control of fuel reduction correction, involves detection of scatter in combustion pressures between cylinders, while at the same time detecting variations in combustion pressure occurring in the same cylinder. The surge-torque level is then detected on the basis of these results.

Abstract: An apparatus and method for controlling an air/fuel mixture ratio for an internal combustion engine which can start the air/fuel mixture ratio at a earlier timing than the conventional air/fuel mixture ratio controlling apparatus. For example, a control unit determines whether the engine is revolved and, thereafter, accumulates an intake air quantity. When the accumulated value exceeds the predetermined value SQ.sub.ST and the control unit determines that the activation of an oxygen sensor sufficiently occurs, the start of the air/fuel mixture ratio feedback control is determined. At this time, a fuel supply quantity T.sub.I is corrected so that the air/fuel mixture ratio which tends to be inclined to a lean side is shifted to the rich side.

Abstract: An incremental correction coefficient K.sub.TW is set according to the temperature Tw of cooling water of an engine and is used to incrementally correct the quantity of fuel injected into the engine. The coefficient K.sub.TW is adjusted according to detected surge torque. An incremental correction coefficient KACC is used during acceleration in the engine, to incrementally correct the quantity of the fuel to be injected and a decremental correction coefficient KDEC is used during deceleration in the engine, to decrementally correct the quantity of the fuel to be injected. The coefficients KACC and KDEC are adjusted according to the degree of the adjustment done on the coefficient K.sub.TW. Not only the coefficient K.sub.TW based on the water temperature but also the coefficients KACC and KDEC based on the acceleration and deceleration are thus corrected to proper levels for the fuel.

Abstract: An apparatus for controlling the engine idling speed to a target value. The apparatus is arranged to calculate a basic engine output torque required to maintain the engine idling speed at a target value, and a required engine output torque change required to change the engine speed to a changed target engine idling speed value. A required engine output torque is calculated based upon the sum of the calculated basic engine output torque and a torque value corresponding to a deviation of a sensed engine output torque change from the required engine output torque change. The required engine output torque is used to control the amount of air permitted to enter the engine when the engine is idling.

Abstract: An air-fuel ratio feedback correction value is used to correct the quantity of fuel supplied to an engine. The correction value is subjected to proportional-integral control to be carried out according to an air-fuel ratio detected by an oxygen sensor according to the oxygen concentration in exhaust. A response delay time occurring in the air-fuel ratio feedback control system is calculated, and according to the response delay time, the air-fuel ratio feedback correction value is adjusted. Even with the response delay time in the feedback control system, an actual air-fuel ratio is substantially converged to a target air-fuel ratio.

Abstract: A fuel delivery control apparatus for use with an internal combustion engine having a throttle valve located in an induction passage for controlling the amount of air to the engine. The engine is associated with an evaporated fuel purging unit having a canister adapted to accumulate evaporated fuel from a fuel tank. A basic value of the amount of fuel metered to the engine is calculated based on the sum of the amount of air supplied to the engine through the throttle valve and the amount of air supplied to the engine from the canister. The basic value is corrected by subtracting the amount of evaporated fuel introduced from the canister to the engine from the calculated basic value. The fuel metered to the engine is controlled based on the corrected basic value.

Abstract: Based on a combustion pressure detected by a cylinder internal pressure sensor, a mean effective pressure Pi is calculated and a fluctuation amount .DELTA.Pi of the mean effective pressure Pi is calculated. The level of a predetermined frequency component of the fluctuation amount .DELTA.Pi is compared with a predetermined level. When the fluctuation amount .DELTA.Pi exceeds the predetermined value, it is judged that an increasing correction coefficient KTW according to a water temperature is smaller than a required value corresponding to a used fuel, and the increasing correction coefficient KTW is increasingly modified. When the above fluctuation amount .DELTA.Pi is less than the predetermined value, it is judged that the increasing correction coefficient KTW is larger than the required value corresponding to the used fuel, and the increasing correction coefficient KTW is decreasingly modified.

Abstract: An apparatus for detecting an intake air quantity for an internal, combustion engine and method therefor are disclosed in which a passed time from a time at which a power supply to a temperature sensitive airflow meter of a bridge circuit is turned on is measured as t. A CPU of the detecting apparatus retrieves a data on the intake air quantity from a data map storing the data on the intake air quantity, the passed time and output voltage of the temperature sensitive airflow meter to derive the intake air quantity data Q.sub.now. In addition, the CPU adds a value of a change rate of the present mapped data with respect to the previously derived final intake air quantity data Q.sub.-1 which is multiplied by a predetermined coefficient k to Q.sub.now. The result of addition is set as the present final intake air quantity data: Q.rarw.Q.sub.now +k (Q.sub.now -Q-.sub.-1). It is noted that the predetermined coefficient k is varied according to the passed time t.

Abstract: Disclosed is an apparatus for detecting the reference rotational angle for each cylinder in a multiple-cylinder internal combustion engine, in which a reference pulse signal is output at a position of a predetermined rotational angle of the engine at a specific stroke of each cylinder synchronously with the revolution of the engine, a cylinder-discriminating pulse signal is put out just after termination of specific one of the reference pulse signal, the precedent and present values of elements, concerning the time, of the pulse signal are detected, and when the present value is smaller than the precedent value by at least a predetermined value, discrimination of cylinders is performed.

Abstract: A driving condition recognition system includes data sampling means, respectively monitoring a plurality of preselected parameters associated with vehicular driving, such as a throttle valve open angle, and engine speed and so forth, for sampling vehicular drive condition associated parameter data within every predetermined period of time. The system also includes means for deriving a vehicle condition evaluating data on the basis of all of the sampled parameter data with respect to each of parameters to be monitored. The system further includes means for evaluating respective an evaluating function set with respect to each parameter for determining satisfying degree relative to the relevent evaluating function. The system further includes means for recognizing vehicle driving condition on the basis of satisfying degree of respective parameters.

Abstract: A fuel supply control system for an internal combustion engine sets an amount of heat generated within a combustion chamber at least based on an engine load condition, and a reference temperature of an exhaust system on the basis of an engine coolant temperature or other parameter associated with the engine coolant temperature. The control system predicts a temperature in the exhaust system based on the set head amount and set reference temperature. The control system derives a correction value for correcting a fuel supply amount on the basis of the predicted temperature of the exhaust system.

Abstract: Sucked air flow quantities are preliminarily alloted and stored for respective areas of predetermined ranges of the driving state of an engine, and every time a new sucked air flow quantity is detected, the stored value is renewed based on the previously stored value and the newly detected value. In the method and apparatus for detecting deterioration of a sucked air flow quantity-detecting device of an engine according to the present invention, the engine driving state is detected and the stored value of the sucked air flow quantity in the corresponding area is retrieved, the retrieved stored value is compared with the sucked air flow quantity actually detected by the detecting device, and deterioration is judged when the difference therebetween is larger than a predetermined value.

Abstract: The present invention relates to a method and apparatus for detecting deterioration of a hot-wire type sucked air flow quantity-detecting device of an engine, in which the change ratio of the output voltage of the hot-wire type sucked air flow quantity-detecting device is measured when the output voltage of the sucked air flow quantity-detecting device is to be changed while the engine is in the substantially non-revolving state, and deterioration is judged by comparing the measured change ratio with a predetermined value, whereby it is possible to exchange parts promptly just in time and prevent degradation of the exhaust gas-purging performance of a vehicle.

Abstract: An inspection device is provided an inspection parameter generator generating predetermined parameter data. The parameter data is transmitted to a control unit subjecting inspection. The inspection device receives input signal from the control unit, which input signal corresponds to the parameter data input to the control unit. Both of the control unit and inspection device processes the corresponding data. The control unit feeds resultant output to the inspection device. The inspection device compares its own resultant data and the resultant output of the control unit to make judgment whether the control unit operates in normal condition or not.

Abstract: Disclosed are a method and apparatus for detecting deterioration of a sucked air flow quantity-detecting device of an engine, in which during a predetermined period after the start of use of the engine, detected values of sucked air flow quantities detected by the sucked air flow quantity-detecting device are learned for respective areas of the engine driving state, and then, the detected value of the sucked air flow quantity detected by the air flow quantity-detecting device is compared with the learned value and deterioration of the sucked air flow quantity-detecting device is judged when the difference is larger than a predetermined value.

Abstract: A fuel supply control system introducing the feature of learning in assuming or projecting an intake air flow rate while an engine driving condition is maintained in a sonic flow range, in which intake air path area is maintained substantially constant and intake air flow rate is varied linearly according to variation of an engine speed. The system also detects the engine driving condition in the sonic flow range and the engine speed maintained substantially constant to derive a basic fuel supply amount on the basis of boost pressure. The assumed intake air flow rate is derived on the basis of the basic fuel supply amount and the engine speed. The system derives the basic fuel supply amount on the basis of the assumed intake air flow rate and the engine speed when the engine speed varies within the sonic flow range.

Abstract: An engine control system introduces a technology of assuming actually required fuel amount to be delivered to each engine cylinder at opening timing of an intake valve of the engine cylinder. In order to derive the assumed fuel demand, a basic fuel supply amount is derived on the basis of a basic fuel supply control parameter including an engine speed data and an intake air amount representative data, an air induction path area variation ratio data and a lag time data from derivation of the air induction path area variation ratio data to opening of the intake valve. The assumed fuel demand data can be used not only for controlling fuel supply but also for spark ignition timing control, air/fuel ratio control and so forth so that the engine operation control may precisely follow the actual engine driving condition for optimizing the engine performance.

Abstract: A fuel supply control system derives a basic induction volume efficiency on the basis of an intake air pressure and modifies the basic induction volume efficiency with a correction value which is derived on the basis of an engine revolution speed and the intake air pressure. An induction volume efficiency is derived on the basis of modified basic induction volume efficiency, which derived induction volume efficiency is used for deriving a basic fuel supply amount with the intake air pressure. The basic fuel supply amount thus derived is used for controlling fuel supply for the engine. Derivation of the basic induction volume efficiency is performed by an interrupt routine which may be executed in a predetermined timing derived depending upon a time or in synchronism with engine revolution cycle. The correction value may be derived in a background job.

Abstract: An air/fuel ratio control system employs an altitude dependent learnt uniform correction coefficient which is applicable for all engine driving range and another engine driving range based correction coefficient learnt with respect to responsive engine driving range. The uniform correction coefficient is cyclically updated on engine driving range based correction coefficient. The control system performs FEEDBACK mode air/fuel ratio control with the learnt uniform correction coefficient and the engine driving range based correction coefficient. On the other hand, the control system performs OPEN LOOP mode air/fuel ratio control with the learnt uniform correction coefficient.