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:
May. 30, 1989
Filed:
Apr. 05, 1988
Toru Hashimoto, Kyoto, JP;
Akira Takahashi, Kyoto, JP;
Takeshi Imaizumi, Anjo, JP;
Susumu Saito, Toyota, JP;
Hiroshi Tanaka, Kyoto, JP;
Takeshi Jimbo, Okazaki, JP;
Mitsubishi Jidosha Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A method of detecting a fault of an exhaust gas recirculation system of an internal combustion engine, comprising detecting a temperature relating to a temperature of a gas recirculating through the exhaust gas recirculation system when the system is in a condition in which the system should be operated to return part of an exhaust gas of the engine to an intake passage, and detecting that the exhaust gas recirculation system is defective when the detected temperature is lower than a fault discriminating value. A condition of air to be sucked into the engine, such as intake air temperature and atmospheric pressure, is detected, and the fault discriminating value is set in accordance with the detected air condition, whereby abnormality or fault of the exhaust gas recirculation system can be detected accurately and reliably. Preferably, the fault detection is inhibited until the engine temperature reaches a predetermined value and/or a predetermined time period elapses after the start-up of the engine, whereby erroneous fault detection can be prevented.