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:
Dec. 12, 2006
Filed:
Jan. 27, 2005
Keiji Wakahara, Inazawa, JP;
Hirofumi Shoda, Toyota, JP;
Keiji Wakahara, Inazawa, JP;
Hirofumi Shoda, Toyota, JP;
Denso Corporation, Kariya, JP;
Abstract
ECU calculates variations of air-fuel ratios of respective cylinders and variations of air-fuel ratios of all the cylinders in variable intake valve lift devices of two cylinder groups. Presence and absence of an abnormality is determined on the basis of whether ratios of variations of air-fuel ratios of respective cylinders to variations of air-fuel ratios of all the cylinders are less than an abnormality threshold. Whether which of variable intake valve lift devices of the cylinder groups is abnormal is determined from control modes of the variable intake valve lift devices of the respective cylinder groups, and the relationship between that cylinder group, to which a cylinder being maximum in air-fuel ratio belongs, and cylinder group, to which a cylinder being minimum in air-fuel ratio belongs.