| 摘要 |
PROBLEM TO BE SOLVED: To avoid the shortage of injection quantity caused by a fuel pressure drop following injection without using a fuel sensor of high responsiveness. SOLUTION: Basic injection pulse width Tp corresponding to reference fuel pressure is computed from an engine operating condition (S1). Fuel pressure P at a time point before injection is read (S2), and the basic injection pulse width Tp is multiplied by a specified fuel pressure drop predictive coefficient K determined from piping capacity, to compute the fuel pressure drop quantityΔP (S3). The fuel pressure drop quantityΔP is subtracted from the fuel pressure P to obtain the after-correction fuel pressure value Pr (S4). The lower limit value of the after-correction fuel pressure value Pr is 0.3 MPa which is reference fuel pressure. On the basis of a previously provided specified characteristic table, an injection rate INJ is determined from the after-correction fuel pressure value Pr (S5). The basic injection pulse width Tp is multiplied by the injection rate INJ to determine final injection pulse width Tr (S6).
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