The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 14, 2004
Filed:
Sep. 19, 2002
Honda Giken Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A failure diagnosis apparatus for diagnosing a failure in an evaporative fuel processing system is disclosed. The evaporative fuel processing system has a fuel tank, a canister containing an adsorbent for adsorbing evaporative fuel generated in the fuel tank, an air passage connected to the canister and communicating with the atmosphere, a first passage for connecting the canister and the fuel tank, a second passage for connecting the canister and an intake system of an internal combustion engine, a vent shut valve for opening and closing the air passage, and a purge control valve provided in the second passage. The purge control valve and the vent shut valve are closed when stoppage of the engine is detected and it is determined whether there is a leak in the evaporative fuel processing system according to the detected pressure in the evaporative fuel processing system during a predetermined determination time period after closing the purge control valve and the vent shut valve. The leak determination of the evaporative fuel processing system is inhibited when the difference between the gas layer temperature and the ambient temperature detected upon stoppage of the engine is less than or equal to a predetermined threshold.