US 12,085,031 B2
Controller and control method for multi-cylinder internal combustion engine
Hitoki Sugimoto, Toyota (JP)
Assigned to Toyota Jidosha Kabushiki Kaisha, Toyota (JP)
Filed by TOYOTA JIDOSHA KABUSHIKI KAISHA, Toyota (JP)
Filed on Nov. 10, 2021, as Appl. No. 17/523,534.
Claims priority of application No. 2020-211814 (JP), filed on Dec. 21, 2020.
Prior Publication US 2022/0195953 A1, Jun. 23, 2022
Int. Cl. F02D 41/00 (2006.01); F02D 41/14 (2006.01); F02D 41/18 (2006.01); F02D 41/22 (2006.01)
CPC F02D 41/0087 (2013.01) [F02D 41/1454 (2013.01); F02D 41/182 (2013.01); F02D 41/22 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A controller for a multi-cylinder internal combustion engine, the multi-cylinder internal combustion engine including an exhaust sensor that detects oxygen and is arranged at an upstream side of a catalyst in an exhaust passage, a first cylinder group including one or more cylinders, and a second cylinder group including one or more cylinders, wherein when an index value corresponding to an intake air amount for the engine is in a predetermined range, with the index value including an engine rotation speed or a charging efficiency, a detection value of the exhaust sensor for oxygen discharged from a cylinder included in the first cylinder group is greater than a detection value of the exhaust sensor for oxygen discharged from a cylinder included in the second cylinder group, the controller comprising:
an execution device, wherein
the execution device is configured to perform:
a specific cylinder fuel cutoff process for performing specific cylinder fuel cutoff control to cut off a supply of fuel to one of cylinders of the multi-cylinder internal combustion engine and supply fuel to the cylinders other than the one cylinder; and
an anomaly determination process for determining whether a cutoff cylinder to which the supply of fuel is cut off is anomalous based on a detection value of the exhaust sensor indicative of an air-fuel ratio that is greater than a predetermined value when the fuel cutoff is normal and less than or equal to the predetermined value when the fuel cutoff is anomalous, and
the specific cylinder fuel cutoff process includes a cutoff cylinder selection process for setting one cylinder of the first cylinder group as the cutoff cylinder, wherein an intake valve and an exhaust valve of the cutoff cylinder open and close in the same manner while the supply of fuel to the cutoff cylinder is cut off as when fuel is supplied to the cutoff cylinder.