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. 12, 2006
Filed:
Mar. 22, 2005
Hiroki Terada, Tokyo, JP;
Hiroki Terada, Tokyo, JP;
Fuji Jukogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A failure diagnostic device for an exhaust gas recirculation (EGR) apparatus, which can detect an intake pipe pressure at a high accuracy with a simple control and can prevent false diagnosis of an EGR system. If at least either one of first and second off-mode intake pipe pressures P, Pexceeds a cancel determination value K, an ECU determines that the intake pipe pressures P, Pand Pare not properly detected, and cancels the failure diagnosis of the EGR system. Therefore, the false diagnosis of the EGR system can be avoided with a simplified process without requiring specific determinations on individual abnormal states of the various components other than the EGR system. By setting the cancel determination value K based on the intake pipe pressure P resulting when EGR off-control is executed in a state of an EGR valve being stuck in a fully-open position, each improperly-detected intake pipe pressure can be excluded with reliability.