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:
Apr. 23, 2013
Filed:
Feb. 11, 2008
Alexander J. Roberts, Commerce Township, MI (US);
Kenneth J. Cinpinski, Ray, MI (US);
Donovan L. Dibble, Utica, MI (US);
Alexander J. Roberts, Commerce Township, MI (US);
Kenneth J. Cinpinski, Ray, MI (US);
Donovan L. Dibble, Utica, MI (US);
Abstract
A method of valve lift failure detection may include determining first and second intake air pressures in an engine having intake valve lifters that selectively operate intake valves in first and second lift modes. The first intake air pressure may correspond to an intake stroke of a first piston of the engine when the engine is commanded to operate in the first lift mode and the second intake air pressure may correspond to an intake stroke of a second piston of the engine when the engine is commanded to operate in the first lift mode. The method may further include determining a difference between the first and second intake air pressures and diagnosing an intake valve lifter failure when the difference exceeds a predetermined limit.