Abstract: A control device for an internal combustion engine can quickly control, regardless of variation of the quantity of evaporative fuel gas adsorbed in a canister of the engine, the air-fuel ratio to a target value by performing air-fuel ratio feedback compensation control so as not to cause the emission performance of the engine to deteriorate. For the first canister purge performed after the engine is started up, a purge valve is driven for a prescribed period at a prescribed purge flow rate. During the period, the quantity of purged fuel is calculated using an air-fuel ratio feedback factor. Based on the fuel quantity thus calculated, an adsorption quantity estimation section estimates the quantity of evaporative fuel gas adsorbed in the canister.

Abstract: The invention provides a method for preferably controlling an internal combustion engine by precisely estimating a current value of a temperature of an exhaust device of an internal combustion engine provided with a variable valve, an exhaust turbo supercharger and the like, and controlling an affector of a temperature of an exhaust gas on the basis of a difference between a reference value of the exhaust device temperature and the current value of the exhaust device temperature.

Abstract: There is provided an engine control device which can accurately calculate a compensation coefficient used for transient compensation of an ignition timing without involving a complicated and large-scale calculation model in order to prevent a combustion deterioration and the like caused by a mechanical response delay and the like of the variable valve timing mechanism at a transition time such as an acceleration/deceleration time.

Abstract: The invention precisely achieves an air fuel ratio control precision in each of operating regions of an engine, particularly a demand air fuel ratio at a time of an engine transition. In a fuel control system correcting a basic fuel amount in such a manner as to estimate a fuel adhered to an air intake pipe of an engine and an evaporated fuel from the adhered fuel so as to achieve a demanded air fuel ratio, a temperature of a fuel adhered portion is estimated on the basis of an amount relation between the fuel to be adhered and the already adhered fuel, or a heat quantity balance. A fuel adhesion amount and a fuel evaporation amount are determined on the basis of the estimated temperature.

Abstract: An apparatus for controlling air-fuel ratio of an internal combustion engine having: a three-way catalytic converter; an oxygen sensor, which is installed at the upstream side of said catalytic converter in respect to exhaust gas flow direction, for generating a switching signal showing rich/lean relative to a certain air-fuel ratio; and an air-fuel ratio sensor, which is installed at the downstream side of said catalytic converter, for generating a linear output signal corresponding to the air-fuel ratio, wherein the apparatus includes a deviation calculation unit for calculating deviation between air-fuel ratio measured by the air-fuel ratio sensor, and target air-fuel ratio; and a feedback control unit of the air-fuel ratio for carrying out feedback control of air-fuel ratio based on the deviation calculated by a deviation calculation unit, and the output signal of the oxygen sensor.

Abstract: A control device for an internal combustion engine can quickly control, regardless of variation of the quantity of evaporative fuel gas adsorbed in a canister of the engine, the air-fuel ratio to a target value by performing air-fuel ratio feedback compensation control so as not to cause the emission performance of the engine to deteriorate. For the first canister purge performed after the engine is started up, a purge valve is driven for a prescribed period at a prescribed purge flow rate. During the period, the quantity of purged fuel is calculated using an air-fuel ratio feedback factor. Based on the fuel quantity thus calculated, an adsorption quantity estimation section estimates the quantity of evaporative fuel gas adsorbed in the canister.

Abstract: Factors affecting the response time of a transfer system from the combustion of injected fuel to the detection of its oxygen concentration include a stroke delay time due to an engine speed, the dependence of an LAF sensor response time on an exhaust gas flow rate, a response time change of the LAF sensor due to its deterioration with time, and the like. If a hyperplane of the sliding mode is fixed without considering the above-mentioned factors affecting the response time of the transfer system, an overshoot or oscillation of a feedback system may occur at low speeds of the engine even if preferable feedback responsiveness can be achieved, for example, at high speeds of the engine. This results in aggravated exhaust emissions, degraded drivability due to torque fluctuations, and fluctuations in idle speed.

Abstract: There is provided an air amount computing unit, and a fuel control unit, of an internal combustion engine that calculates a cylinder flow-in air amount during a transient state without response delay and so as not to have any inflection point in changes of flow rate and that allows a desirable air-fuel ratio to be kept.

Abstract: Air quantity of ISC is roughly controlled on the basis of the lift amount of an intake valve, whose air flow rate control range is wide. The adjustment of the air quantity beyond the range of the rough control is achieved by the control based on a phase of the intake valve. As a result, a required flow rate can be achieved with high accuracy. If only the intake-valve lift amount whose air flow rate control range is wide is used to achieve the required air quantity of ISC, a fuel control system requires both a high degree of accuracy of an intake-valve lift amount sensor and a high degree of accuracy of an intake-valve lift amount control mechanism itself, which leads to high system costs. The air quantity of ISC is roughly controlled on the basis of the intake-valve lift amount whose air flow rate control range is wide (the air quantity is controlled based on an air flow rate corresponding to each integral multiple of the air flow rate control minimum resolution).

Abstract: The invention precisely achieves an air fuel ratio control precision in each of operating regions of an engine, particularly a demand air fuel ratio at a time of an engine transition. In a fuel control system correcting a basic fuel amount in such a manner as to estimate a fuel adhered to an air intake pipe of an engine and an evaporated fuel from the adhered fuel so as to achieve a demanded air fuel ratio, a temperature of a fuel adhered portion is estimated on the basis of an amount relation between the fuel to be adhered and the already adhered fuel, or a heat quantity balance. A fuel adhesion amount and a fuel evaporation amount are determined on the basis of the estimated temperature.

Abstract: An engine controller of the present invention is comprised of: a determining section for determining a state where an engine is not driven; a braking torque obtaining section for obtaining a braking toque acting on the vehicle; a vehicle speed sensing section for sensing a vehicle speed; an atmospheric pressure obtaining section for obtaining an atmospheric pressure value when an engine is driven; a road gradient obtaining section for obtaining a road gradient on the basis of the braking torque and the vehicle speed when the determining section determines the state where the vehicle is not driven; an atmospheric pressure correcting section which calculates a vehicle vertical travel of a downhill on the basis of the road gradient and a travel distance derived from the vehicle speed when the vehicle has descended the downhill, and corrects the atmospheric pressure value on the basis of the vehicle vertical travel of the downhill.

Abstract: At the start-up of an engine, the ignition timing and the air-fuel ratio are controlled to prevent overload onto the volume of ISC air and decreased torque and torque difference. The fuel condition based on the amount of ignition timing correction to inhibit rotational fluctuation during idling is determined and the fuel quantity based on the result is corrected. Right after an engine has started and until a pilot burner is created in the heat spot of the catalyst, the ignition retard control is mainly executed, and at the time when it is determined that a pilot burner has been created in the catalyst's heat spot, the lean air-fuel ratio control is to be executed instead of the ignition retard control. Furthermore, when the ignition retard control changes to the lean air-fuel ratio control, the state transition control is executed along the equivalent ISC air volume line so as not to cause torque fluctuation.

Abstract: There is provided an air amount computing unit, and a fuel control unit, of an internal combustion engine that calculates a cylinder flow-in air amount during a transient state without response delay and so as not to have any inflection point in changes of flow rate and that allows a desirable air-fuel ratio to be kept.

Abstract: A fuel control system for a cylinder direct injection internal combustion engine. A predetermined portion of the fuel spray is appropriately ignited regardless of the correction of the ignition timing, thereby always securing stable, satisfactory combustion. In the case where the ignition timing is corrected, the fuel injection timing is corrected in accordance with the ignition timing correction amount. The fuel injection timing is corrected also with the change in the internal cylinder pressure and the fuel injection velocity taking the intake pipe pressure and the fuel pressure into account, thereby maintaining the required ignition point of the fuel spray.

Abstract: A fuel control system for a cylinder direct injection internal combustion engine. A predetermined portion of the fuel spray is appropriately ignited regardless of the correction of the ignition timing, thereby always securing stable, satisfactory combustion. In the case where the ignition timing is corrected, the fuel injection timing is corrected in accordance with the ignition timing correction amount. The fuel injection timing is corrected also with the change in the internal cylinder pressure and the fuel injection velocity taking the intake pipe pressure and the fuel pressure into account, thereby maintaining the required ignition point of the fuel spray.

Abstract: An engine controller of the present invention is comprised of: a determining section for determining a state where an engine is not driven; a braking torque obtaining section for obtaining a braking toque acting on the vehicle; a vehicle speed sensing section for sensing a vehicle speed; an atmospheric pressure obtaining section for obtaining an atmospheric pressure value when an engine is driven; a road gradient obtaining section for obtaining a road gradient on the basis of the braking torque and the vehicle speed when the determining section determines the state where the vehicle is not driven; an atmospheric pressure correcting section which calculates a vehicle vertical travel of a downhill on the basis of the road gradient and a travel distance derived from the vehicle speed when the vehicle has descended the downhill, and corrects the atmospheric pressure value on the basis of the vehicle vertical travel of the downhill.

Abstract: An apparatus for diagnosing deterioration of a catalyst for an internal combustion engine, having a first catalyst and a second catalyst and provided with sensors for detecting a particular exhaust component before and after the first catalyst, wherein a relationship between a deterioration property involved in clarification of an exhaust gas of the internal combustion engine by a combination of the first catalyst and the second catalyst and a deterioration property of the first catalyst are determined previously; a deterioration degree of the first catalyst is calculated according to outputs from the sensors disposed before and after the first catalyst; deterioration of the first catalyst is judged according to the deterioration degree; and deterioration of the second catalyst is judged according to the deterioration degree of the first catalyst.

Abstract: When an updating event occurs, an information management base station unit inquires all the vehicles under its management about the presence or absence of vehicle-mounted control units to be updated. Based on replies from the individual vehicles, the information management base station unit selects the vehicles to be updated, and then it automatically updates them via wireless communication.

Abstract: An apparatus for controlling air-fuel ratio of an internal combustion engine having: a three-way catalytic converter; an oxygen sensor, which is installed at the upstream side of said catalytic converter in respect to exhaust gas flow direction, for generating a switching signal showing rich/lean relative to a certain air-fuel ratio; and an air-fuel ratio sensor, which is installed at the downstream side of said catalytic converter, for generating a linear output signal corresponding to the air-fuel ratio, wherein the apparatus includes a deviation calculation unit for calculating deviation between air-fuel ratio measured by the air-fuel ratio sensor, and target air-fuel ratio; and a feedback control unit of the air-fuel ratio for carrying out feedback control of air-fuel ratio based on the deviation calculated by a deviation calculation unit, and the output signal of the oxygen sensor.

Abstract: A fuel control system for a cylinder direct injection internal combustion engine. A predetermined portion of the fuel spray is appropriately ignited regardless of the correction of the ignition timing, thereby always securing stable, satisfactory combustion. In the case where the ignition timing is corrected, the fuel injection timing is corrected in accordance with the ignition timing correction amount. The fuel injection timing is corrected also with the change in the internal cylinder pressure and the fuel injection velocity taking the intake pipe pressure and the fuel pressure into account, thereby maintaining the required ignition point of the fuel spray.