Abstract: An electronic control unit detects a manner of fluctuation of a fuel pressure with injection of fuel by a fuel injection valve with the use of a fuel pressure sensor, and calculates a tendency of deviation of an actual fuel injection characteristic of the fuel injection valve with respect to a basic fuel injection characteristic on the basis of a result of comparison between a detected temporal waveform and a basic temporal waveform. The tendency of deviation is reflected at a predetermined reflection rate (R) at the time of updating a learned value (Gij) for compensating for an individual difference of the fuel injection valve. The predetermined reflection rate (R) is increased when an accumulated value (D) of a vehicle travel distance is shorter than a predetermined value (Dth) as compared with when the accumulated value (D) is longer than or equal to the predetermined value (Dth).

Abstract: An electronic control unit, in an idle operating state, detects a crankshaft rotation fluctuation in each cylinder using a crank angle sensor, and updates an individual correction value for a control value for each fuel injection valve as a first learned value such that a degree of deviation in the crankshaft rotation fluctuation among the cylinders reduces. The electronic control unit uses a fuel pressure sensor to detect a manner of a fuel pressure fluctuation with fuel injection by each fuel injection valve, and updates an individual correction value for a control value for each fuel injection valve as a second learned value based on a result of comparison between a detected temporal waveform and a basic temporal waveform. In an idle operating state, a learning rate of the second learned value is reduced until the first learned value converges for the first time as compared with after its convergence.

Abstract: An electronic control unit, in an idle operating state, detects a crankshaft rotation fluctuation in each cylinder using a crank angle sensor, and updates an individual correction value for a control value for each fuel injection valve as a first learned value such that a degree of deviation in the crankshaft rotation fluctuation among the cylinders reduces. The electronic control unit uses a fuel pressure sensor to detect a manner of a fuel pressure fluctuation with fuel injection by each fuel injection valve, and updates an individual correction value for a control value for each fuel injection valve as a second learned value based on a result of comparison between a detected temporal waveform and a basic temporal waveform. In an idle operating state, a learning rate of the second learned value is reduced until the first learned value converges for the first time as compared with after its convergence.

Abstract: An electronic control unit detects a manner of fluctuation of a fuel pressure with injection of fuel by a fuel injection valve with the use of a fuel pressure sensor, and calculates a tendency of deviation of an actual fuel injection characteristic of the fuel injection valve with respect to a basic fuel injection characteristic on the basis of a result of comparison between a detected temporal waveform and a basic temporal waveform. The tendency of deviation is reflected at a predetermined reflection rate (R) at the time of updating a learned value (Gij) for compensating for an individual difference of the fuel injection valve. The predetermined reflection rate (R) is increased when an accumulated value (D) of a vehicle travel distance is shorter than a predetermined value (Dth) as compared with when the accumulated value (D) is longer than or equal to the predetermined value (Dth).

Abstract: Based on a detection signal of a fuel pressure sensor provided in a first fuel injector, an ECU determines whether a fuel pressure in a first fuel injector is increased over a specified amount when a second fuel injector provided with no fuel pressure sensor terminates a fuel injection. When the ECU determines that the fuel pressure in the first fuel injector is increased over a specified amount, it is diagnosed that the second fuel injector does not have a malfunction of continuous injection.

Abstract: Based on a detection signal of a fuel pressure sensor provided in a first fuel injector, an ECU determines whether a fuel pressure in a first fuel injector is increased over a specified amount when a second fuel injector provided with no fuel pressure sensor terminates a fuel injection. When the ECU determines that the fuel pressure in the first fuel injector is increased over a specified amount, it is diagnosed that the second fuel injector does not have a malfunction of continuous injection.

Abstract: A control apparatus is provided to control a fuel injection apparatus. The fuel injection apparatus includes an accumulator that accumulates high-pressure fuel, at least one injector that injects the high-pressure fuel accumulated in the accumulator into a cylinder of an internal combustion engine, and a pressure sensor that senses fuel pressure in the accumulator and outputs a signal indicative of the sensed fuel pressure. The control apparatus includes an estimator, a determiner, and a setter. The estimator estimates an actual injection duration of the injector. The determiner determines, during the actual injection duration estimated by the estimator, a value of the fuel pressure in the accumulator based on the signal output from the pressure sensor. The setter sets a manipulated variable for controlling fuel injection quantity of the injector based on the value of the fuel pressure determined by the determiner.

Abstract: A control apparatus is provided to control a fuel injection apparatus. The fuel injection apparatus includes an accumulator that accumulates high-pressure fuel, at least one injector that injects the high-pressure fuel accumulated in the accumulator into a cylinder of an internal combustion engine, and a pressure sensor that senses fuel pressure in the accumulator and outputs a signal indicative of the sensed fuel pressure. The control apparatus includes an estimator, a determiner, and a setter. The estimator estimates an actual injection duration of the injector. The determiner determines, during the actual injection duration estimated by the estimator, a value of the fuel pressure in the accumulator based on the signal output from the pressure sensor. The setter sets a manipulated variable for controlling fuel injection quantity of the injector based on the value of the fuel pressure determined by the determiner.