| 摘要 |
<P>PROBLEM TO BE SOLVED: To enable accurate learning of atmospheric pressure without using an atmospheric pressure sensor, in regard to an atmospheric pressure learning device mounted on an automobile having an evaporation fuel treatment system for combustion treatment in an internal combustion engine and an abnormality diagnostic device. <P>SOLUTION: A selector valve 152 for making a canister 46 communicated/shielded with/from the atmosphere is provided on an atmospheric pressure side passage 144c connected to the canister 146. A pressure sensor 154 is mounted inside the passage in the canister 146 side from the selector valve 152, and a pump 156 is arranged so as to introduce negative pressure into inside of the passage. Abnormalities such as fuel leakage are detected, based on a pressure value from the pressure sensor 154 when the pump 156 is driven by closing a solenoid valve 142 for sealing and a solenoid valve 148 for purging and by switching the selector valve 152 to a state where the passage in the canister 146 side is shielded from the atmosphere. When the selector valve 152 is switched to a state where the passage in the canister 146 side communicates with the atmosphere, learning of the atmospheric pressure is performed by using the pressure value from the pressure sensor 154. Accordingly, the learning of the atmospheric pressure can be performed accurately without using an atmospheric pressure sensor. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
