| 摘要 |
PROBLEM TO BE SOLVED: To shorten the time for leak diagnostic in evaporative fuel processor. SOLUTION: After an engine stop, an air pump 13 is actuated and a directional control valve 14 is changed over to connection with the air pump 13, so that the air the air pump 13 force-feeds flows through the directional control valve 14 and into a new charge inlet 9 of a canister 7 which feeds it into purge lines 6 and 10. The air pump 13 is initially driven on a high driving voltage V2 so as to have an accordingly raised feed rate. The driving voltage of the air pump 13 is next changed down to a normal driving voltage V1, after which the operating current value of the air pump 13 is measured as a leak level. The obtained leak level is compared with a determination level. A leak level not larger than the determination level triggers a leak decision.
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