| 摘要 |
PURPOSE: To identify a rough road section with an existing sensor without using an expensive sensor or a special sensor by detecting the tank pressure value at consecutive evaluation time points to obtain the change value of tank pressure. CONSTITUTION: The tank pressure value TDn supplied from a sensor is detected and intermediately stored so as to form the absolute value DTD of the difference between two consecutive tank pressure value measured immediately before. This differential absolute value DTD is averaged MDTD, and the averaged differential value MDTD is compared with the threshold vague GW. This threshold value GW is taken out of a characteristic curve stage depending on the instantaneous vehicle speed and an instantaneous tank filling level, for instance. In case of the averaged differential value MDTD being larger than the threshold value GW, a rough road section is displayed, and the identification of a combustion failure state is made non-effective. In case of the averaged differential value MDTD being smaller than or equal to the threshold value, no rough road section exist, and the identification of the combustion failure state is not made non-effective. |
