Kraftstoffdruckkurvenverlauf-Aufnahmevorrichtung

摘要

A fuel injection system has a fuel injector and a fuel pressure sensor. An ECU acquires a pressure waveform detected by the fuel pressure sensor during performing a multi-stage injection as a detected waveform at the time of the multi-stage injection, memorizes a model waveform, which is used as a standard of the pressure waveform when an injection that is preceding an target injection is performed without performing the target injection when any one of an injection of a second stage or later of an injection is considered as the target injection among multi-stage injections, and extracts the pressure waveform resulting from the target injection by deducting the model waveform from the detected waveform at the multi-stage injection. The ECU corrects the model waveform used for extraction by a ratio according to a maximum injection rate in the injection of the preceding stage.