Abstract: A fuel injection control device is a control device controlling an injection of fuel by a fuel injector and includes: a setting part that sets a request injection quantity of an injection quantity requested of the fuel injector; a dividing part that divides the request injection quantity set by the setting part into a specified injection quantity and an adjusting injection quantity other than the specified injection quantity; an injection performing part that performs a dividing injection of an adjusting injection and a partial lift injection by the fuel injector, the adjusting injection injecting the adjusting injection quantity of fuel, the partial lift injection finishing a lift of a valve body of the fuel injector in a partial lift state before the valve body reaching a full lift position and injecting the specified injection quantity of fuel; and a learning part that learns an injection characteristic of the fuel injector at the time of the partial lift injection.

Abstract: An inter-connect circuit (ICC) device for a fuel delivery system of a vehicle is disposed between an engine control unit (ECU) and a fuel control device. The ECU transmits a drive pulse to the fuel control device by way of a drive pulse line passing through the ICC device. The ICC device includes a housing and a sense circuit. The housing has a first side that is connectable to the ECU and a second side different from the first side that is connectable to the fuel control device. The sense circuit is disposed within the housing. The sense circuit is electrically coupled to the drive pulse line by way of a sense circuit line and is communicably coupled to the ECU by way of a data communication line.

Abstract: At least after off of an injection pulse of partial lift injection, a first filtered voltage Vsm1 being a negative terminal voltage Vm of a fuel injection valve filtered by a first low-pass filter having a first frequency f1 as a cutoff frequency, the first frequency f1 being lower than a frequency of a noise component, is acquired, and a second filtered voltage Vsm2 being the negative terminal voltage Vm filtered by a second low-pass filter having a second frequency f2 as a cutoff frequency, the second frequency f2 being lower than the first frequency f1, is acquired. Time from a predetermined reference timing to a timing when a difference Vdiff (=Vsm1?Vsm2) between the filtered voltages has an inflection point is calculated as voltage inflection time Tdiff, and the injection pulse of the partial lift injection is corrected based on the voltage inflection time Tdiff.

Abstract: After off of an injection pulse of partial lift injection, a first filtered voltage Vsm1 being a negative terminal voltage of a fuel injection valve filtered by a first low-pass filter and a second filtered voltage Vsm2 being the negative terminal voltage of the fuel injection valve filtered by a second low-pass filter are calculated, and time from a predetermined reference timing to a timing when a difference Vdiff (=Vsm1?Vsm2) between the filtered voltages has an inflection point is calculated as voltage inflection time Tdiff. An averaged value Tdiff.ave of a predetermined frequency of data of the voltage inflection time Tdiff is obtained as a learning value of the voltage inflection time, and the injection pulse of the partial lift injection is corrected based on the learning value Tdiff.ave of the voltage inflection time.

Abstract: At least after off of an injection pulse of partial lift injection, a difference between a first filtered voltage being a negative terminal voltage of a fuel injection valve filtered by a first low-pass filter and a second filtered voltage being the terminal voltage filtered by a second low-pass filter is calculated, and time from a predetermined reference timing to a timing when the difference between the filtered voltages has an inflection point is calculated as voltage inflection time. Subsequently, an injection quantity corresponding to current voltage inflection time is estimated for each of injection pulse widths with a relationship between the voltage inflection time and the injection quantity, the relationship being beforehand stored for each of the injection pulse widths.

Abstract: An inter-connect circuit (ICC) device for a fuel delivery system of a vehicle is disposed between an engine control unit (ECU) and a fuel control device. The ECU transmits a drive pulse to the fuel control device by way of a drive pulse line passing through the ICC device. The ICC device includes a housing and a sense circuit. The housing has a first side that is connectable to the ECU and a second side different from the first side that is connectable to the fuel control device. The sense circuit is disposed within the housing. The sense circuit is electrically coupled to the drive pulse line by way of a sense circuit line and is communicably coupled to the ECU by way of a data communication line.

Abstract: A cylinder-inflow EGR gas amount is estimated, a misfire limit EGR gas amount is calculated on the basis of an engine operation state, and the misfire limit EGR gas amount is compared with the cylinder-inflow EGR gas amount to predict whether a misfire occurs. When the misfire is predicted, a misfire avoidance control is executed. Further, an actual misfire countermeasure effect amount in a case of the execution of the misfire avoidance control is calculated, and the actual misfire countermeasure effect amount is compared with a required misfire countermeasure effect amount to determine whether the misfire is avoidable when the misfire avoidance control is executed. If the misfire is unavoidable even if the misfire avoidance control is executed, a delay restriction value of an ignition timing to avoid the misfire is calculated, and the amount of a delay in the ignition timing is restricted using the delay restriction value.

Abstract: In an EGR system, a quantity of exhaust gas passing through an EGR valve is computed by an EGR valve model simulating a behavior of the recirculated exhaust gas passing through the EGR valve. An exhaust gas quantity flowing into a cylinder is computed by an EGR-gas-delay model simulating a behavior of the exhaust gas passing through the EGR valve and the throttle valve and then flows into a cylinder. The EGR-gas-delay model includes a confluent-delay model simulating a behavior of EGR gas passing thorough the EGR valve and flowing into the intake passage upstream of the throttle valve; an intake-pipe-delay model simulating a behavior of EGR gas flowing in the intake passage and passing through the throttle valve; and an intake-manifold-delay model simulating a behavior of EGR gas which passes through the throttle valve and then flows into the intake passage downstream of the throttle valve.

Abstract: A fuel injection control device is a control device controlling an injection of fuel by a fuel injector and includes: a setting part that sets a request injection quantity of an injection quantity requested of the fuel injector; a dividing part that divides the request injection quantity set by the setting part into a specified injection quantity and an adjusting injection quantity other than the specified injection quantity; an injection performing part that performs a dividing injection of an adjusting injection and a partial lift injection by the fuel injector, the adjusting injection injecting the adjusting injection quantity of fuel, the partial lift injection finishing a lift of a valve body of the fuel injector in a partial lift state before the valve body reaching a full lift position and injecting the specified injection quantity of fuel; and a learning part that learns an injection characteristic of the fuel injector at the time of the partial lift injection.

Abstract: EGR gas quantity information, which indicates a quantity of the EGR gas flowing into a cylinder of an internal combustion engine, is obtained by an ECU. A combustion stop delay control operation, which delays execution of a combustion stop control operation, is executed by the ECU when the quantity of the EGR gas flowing into the cylinder is larger than a normal combustion determination threshold value. When the quantity of the EGR gas flowing into the cylinder becomes equal to or smaller than the normal combustion determination threshold value, the combustion stop control operation is enabled by the ECU.

Abstract: While an engine is an idling state and an EGR opening degree is increased stepwise from a specified opening degree, a variation in engine speed (a standard deviation in engine speed) is repeatedly computed. After that, a specified step amount is successively reduced from the EGR opening degree and the variation in engine speed is successively computed until the EGR opening degree becomes less than or equal to a specified value. Then, a maximum value of the EGR opening degrees where the variation in engine speed becomes minimum is learned as the full-close position.

Abstract: At least after off of an injection pulse of partial lift injection, a difference between a first filtered voltage being a negative terminal voltage of a fuel injection valve filtered by a first low-pass filter and a second filtered voltage being the terminal voltage filtered by a second low-pass filter is calculated, and time from a predetermined reference timing to a timing when the difference between the filtered voltages has an inflection point is calculated as voltage inflection time. Subsequently, an injection quantity corresponding to current voltage inflection time is estimated for each of injection pulse widths with a relationship between the voltage inflection time and the injection quantity, the relationship being beforehand stored for each of the injection pulse widths.

Abstract: After off of an injection pulse of partial lift injection, a first filtered voltage Vsm1 being a negative terminal voltage of a fuel injection valve filtered by a first low-pass filter and a second filtered voltage Vsm2 being the negative terminal voltage of the fuel injection valve filtered by a second low-pass filter are calculated, and time from a predetermined reference timing to a timing when a difference Vdiff (=Vsm1?Vsm2) between the filtered voltages has an inflection point is calculated as voltage inflection time Tdiff. An averaged value Tdiff.ave of a predetermined frequency of data of the voltage inflection time Tdiff is obtained as a learning value of the voltage inflection time, and the injection pulse of the partial lift injection is corrected based on the learning value Tdiff.ave of the voltage inflection time.

Abstract: At least after off of an injection pulse of partial lift injection, a first filtered voltage Vsm1 being a negative terminal voltage Vm of a fuel injection valve filtered by a first low-pass filter having a first frequency f1 as a cutoff frequency, the first frequency f1 being lower than a frequency of a noise component, is acquired, and a second filtered voltage Vsm2 being the negative terminal voltage Vm filtered by a second low-pass filter having a second frequency f2 as a cutoff frequency, the second frequency f2 being lower than the first frequency f1, is acquired. Time from a predetermined reference timing to a timing when a difference Vdiff (=Vsm1?Vsm2) between the filtered voltages has an inflection point is calculated as voltage inflection time Tdiff, and the injection pulse of the partial lift injection is corrected based on the voltage inflection time Tdiff.

Abstract: When a given learning performance condition is met, a partial lift injection for opening a fuel injector is performed by an injection pulse which brings about a partial lift state in which a lift quantity of a valve body of the fuel injector does not reach a full lift position, and an integrated value of a drive current is calculated which flows through a drive coil of the fuel injector after an injection pulse of the partial lift injection is turned off. An inductance of the drive coil is calculated in consideration of a direct current superposition characteristic of the drive coil on the basis of the integrated value of the drive current, whereby the inductance of the drive coil is calculated with high accuracy. Then, the lift quantity of the valve body is estimated on the basis of the inductance, whereby the lift quantity of the valve body is estimated with high accuracy.

Abstract: A first purge passage is connected to an intake-air passage at a downstream side of a throttle valve. A second purge passage is connected to the intake-air passage at an upstream side of a supercharging device. A first and a second check valve are respectively provided in the first and second purge passages. A control unit determines to which operating condition (from a first to a third operating condition) engine operation corresponds, based on downstream-side and upstream-side pressure of the throttle valve. A change of in-tank pressure of a fuel tank is detected in a condition that an air-communication valve is closed but a purge control valve is opened. The control unit diagnoses which of the valves is not normally operated and whether such valve is fixed to a valve opened or a valve closed position, based on the change of in-tank pressure for each of engine operating conditions.

Abstract: A cylinder-inflow EGR gas quantity determining arrangement estimates or senses a value of a cylinder-inflow EGR gas quantity, which is a quantity of EGR gas that flows into a cylinder of an internal combustion engine. A misfire predicting arrangement predicts whether misfire occurs based on the value of the cylinder-inflow EGR gas quantity and an operational state of the internal combustion engine. A misfire-avoidance control arrangement executes at least one misfire-avoidance control operation to avoid the misfire when the misfire predicting arrangement predicts that the misfire occurs.

Abstract: A deterioration diagnosis device, which performs a deterioration diagnosis of a catalyst, includes an exhaust-gas sensor provided downstream of the catalyst in a flow direction of exhaust gas such that an output value of the exhaust-gas sensor is used at least in the deterioration diagnosis. The deterioration diagnosis device further includes the constant current supply portion which applies a voltage to a sensor element of the exhaust-gas sensor to change an output characteristic of the exhaust-gas sensor, a response-time detection portion which detects a response time required for the output value of the exhaust-gas sensor to change from a rich threshold to a lean threshold, a response-time correction portion which controls the constant current supply portion to change the output characteristic of the exhaust-gas sensor so as to shorten the response time when the response time is longer than a predetermined reference time.

Abstract: When a constant driving voltage is applied to a motor driving an EGR valve so that the EGR opening degree is varied, an angular speed of the EGR valve becomes minimal at a position where the driving torque of the EGR valve becomes maximal. In view of this, while an opening degree of the EGR valve is varied with a constant driving voltage applied to the motor, the EGR opening degree where the angular speed becomes minimal is learned as a full-close position.

Abstract: A fuel injection control device for an engine executes a split injection constructed by a fixed injection and a variable injection. A required injection amount of the fixed injection is set in a low range. A required injection amount of the variable injection is set in a high range. An injection amount in the high range is larger than that of the low range. The required injection amount of the variable injection is changed within the high range while the required injection amount of the fixed injection is fixed when a load of the engine is varied while the split injection is performed. An injection control characteristic is corrected based on an actual air-fuel ratio detected before the load is varied and an actual air-fuel ratio detected after the load is varied.