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:
Jun. 17, 1997
Filed:
Jun. 26, 1996
Peter Lautenschutz, Plochingen, DE;
Mercedes-Benz AG, , DE;
Abstract
The invention provides a process for diagnosing defects in an exhaust gas recirculation device of an internal-combustion engine system having an engine timing gear with a knock control. According to the invention, the firing point is advanced until a predetermined minimal knock control displacement is reached, at a time when the engine is operating in steady-state conditions and the exhaust gas recirculation device is active. Subsequently, the exhaust gas recirculation rate is reduced while the advanced firing point is maintained, and it is determined whether the knock control frequency or the knock control displacement change. If not, a defect in the exhaust gas recirculation device is concluded.