| 摘要 |
PROBLEM TO BE SOLVED: To precisely grasp the pressure within an accumulator and improve the exhaust gas characteristic by detecting the pressure within the accumulator within a specified period from the end of fuel injection of an injection valve to the start of injection in the fuel injection valve of the next cylinder after the lapse of a prescribed time from it, and drive-controlling the injection valve on the basis of the detected pressure. SOLUTION: During the operation of an engine, an ECU 5 detects the engine speed on the basis of the output of a crank angle sensor 21, judges exhaust mode or not, and calculates an average rail pressure Pc from the output of a rail pressure sensor 15 for detecting the pressure of a common rail (accumulator) 3 when the exhaust mode is not selected. The current-carrying time to an injector control valve 4a is calculated from the resulting average rail pressure Pc and a target injection quantity based on the engine operating state to perform a fuel injection. On the other hand, when the exhaust mode is selected, only the rail pressure Pcr in 90 deg.-BTDC is measured, and the current-carrying time to the injector control valve 4a is calculated from this value and the intended injection quantity to perform the fuel injection.
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