| 摘要 |
PROBLEM TO BE SOLVED: To provide an evaporative fuel treatment device capable of decreasing the actuation frequency of a purge pump and preventing the stopped purge pump from disturbing an evaporative fuel purge treatment.SOLUTION: An evaporative fuel treatment device actuates a purge pump 7 in a "pump actuation region" low in an intake negative pressure to perform a purge treatment, and stops the purge pump 7 in a "pump stop region" that is not low in the intake negative pressure to perform a vapor treatment by opening a bypass passage 8. Since the purge pump 7 is actuated in response to a state of generation of the intake negative pressure, it is possible to decrease the actuation frequency of the purge pump 7. Furthermore, since the purge treatment is performed via the bypass passage 8 in the "pump stop region", it is possible to eliminate a problem that the stopped purge pump 7 acts as a high ventilation resistance and ensure a necessary purge amount by the intake negative pressure generated in an intake passage 3. |
