US 12,117,366 B2
Diagnosing apparatus and diagnosing method for internal combustion engine
Yuki Ikejiri, Nishio (JP); and Akihiro Katayama, Toyota (JP)
Assigned to TOYOTA JIDOSHA KABUSHIKI KAISHA, Toyota (JP)
Filed by TOYOTA JIDOSHA KABUSHIKI KAISHA, Toyota (JP)
Filed on Jun. 5, 2023, as Appl. No. 18/328,905.
Claims priority of application No. 2022-093070 (JP), filed on Jun. 8, 2022.
Prior Publication US 2023/0400386 A1, Dec. 14, 2023
Int. Cl. G01M 15/11 (2006.01); F02D 41/00 (2006.01); F02D 41/22 (2006.01); F02D 41/38 (2006.01)
CPC G01M 15/11 (2013.01) [F02D 41/0087 (2013.01); F02D 41/22 (2013.01); F02D 41/38 (2013.01); F02D 2041/224 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A diagnosing apparatus for an internal combustion engine, wherein the internal combustion engine is configured to execute a specific-cylinder fuel cutoff process in which combustion in part of cylinders is stopped and combustion is continued in the remaining cylinders, and the diagnosing apparatus comprises
a processing circuitry, wherein the processing circuitry is configured to execute
a misfire anomaly diagnosing process of diagnosing whether there is a misfire anomaly in the internal combustion engine based on a misfire frequency of the internal combustion engine, and
a normality restoration diagnosing process of diagnosing, in a state in which it is diagnosed that there is a misfire anomaly, that the misfire anomaly has been resolved when a measured value of the misfire frequency becomes less than or equal to a specified normality restoration determination value, and
the normality restoration diagnosing process is configured to stop measurement of the misfire frequency and to not diagnose, during the execution of the specific-cylinder fuel cutoff process, that the misfire anomaly has been eliminated.