| 摘要 |
An apparatus extracts a main waveform component and a branch waveform component from a pressure waveform detected by a fuel pressure sensor. The main waveform component is caused by pressure change traveling in a main passage. The branch waveform component is caused by pressure change traveling in a branch passage. The apparatus calculates traveling speeds based on the components. Then, the apparatus estimates a main passage temperature based on a detected value of the fuel temperature sensor, the traveling speeds, the fuel pressure waveform and an average pressure. |
