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. 27, 2016
Filed:
Jul. 03, 2014
Continental Automotive Systems, Inc., Auburn Hills, MI (US);
Ningsheng Qiao, Troy, MI (US);
Chandrasekar Krishnamuthy, Canton, MI (US);
David Frankowski, Monroe, MI (US);
Michael Kalich, Sterling Heights, MI (US);
Continental Automotive Systems, Inc., Auburn Hills, MI (US);
Abstract
A system and method for detecting air-fuel ratio rich-lean imbalance in an automotive engine cylinder is provided. The system and the method are configured to receive an oxygen sensor voltage of an oxygen sensor. They also include filtering the oxygen sensor voltage to create a filtered oxygen sensor voltage. An engine speed and load are determined, and an air-fuel ratio imbalance detection threshold is determined based on the engine speed and the engine load. A rich-lean imbalance status is determined, the rich-lean imbalance status being non-normal if any portion of the filtered oxygen sensor voltage exceeds the air-fuel ratio imbalance detection threshold, and the rich-lean imbalance status being normal if none of the filtered oxygen sensor voltage exceeds the air-fuel ratio imbalance detection threshold. An engine control unit having several control logics to execute similar steps is also provided.