Abstract: In the exhaust gas control system, the electronic control unit is configured to execute first air-fuel ratio control for controlling an air-fuel ratio of an air-fuel mixture in a part of cylinders to a lean air-fuel ratio and controlling an air-fuel ratio of an air-fuel mixture in the other part of the cylinders to a rich air-fuel ratio is executed. The electronic control unit is configured to execute second air-fuel ratio control to perform malfunction diagnosis. The electronic control unit is configured to execute second air-fuel ratio control when the execution of the first air-fuel ratio control is interrupted after the temperature of the three-way catalyst becomes equal to or higher than the diagnosis temperature.

Abstract: An abnormality in an exhaust system component disposed at the downstream side of a particulate filter is determined by using a differential pressure sensor for measuring a differential pressure between a pressure of exhaust gas at the upstream side of the particulate filter and an atmospheric pressure.

Abstract: A control method for an internal combustion engine having a plurality of cylinders and a filter provided in an exhaust passage of the internal combustion engine in order to collect particulate matter. The control method includes a partial cylinder stoppage step, in which a supply of fuel is stopped in a part of a plurality of cylinders while continuing to supply fuel to the other cylinders such that combustion is performed therein, is implemented after a request to stop an internal combustion engine is issued but before the internal combustion engine is stopped, and after the partial cylinder stoppage step, an all cylinder stoppage step is implemented to stop the internal combustion engine by stopping the supply of fuel in all of the cylinders.

Abstract: An exhaust passage of an internal combustion engine is provided with an upstream side three-way catalyst capable of purifying exhaust gas and a particulate filter (PM filter) for trapping particulate matter PM contained in exhaust gas. Catalyst warm-up control is exercised for the purpose of warming up mainly the upstream side three-way catalyst at cold start. Filter regeneration control for removing the particulate matter PM accumulating on the particulate filter from the filter is exercised at the cold start after the catalyst warm-up control is exercised.

Abstract: An internal combustion engine is provided that performs stoichiometric burn operation under control for providing a stoichiometric air-fuel ratio as basic control for an air-fuel ratio. A particulate filter (PM filter) is provided in an exhaust passage of the engine to trap particulate matter PM contained in exhaust gas. If it is judged that the PM filter will have excessively elevated temperature, fuel cut is prohibited during deceleration. Otherwise, before the prohibition of the fuel cut, the air-fuel ratio of exhaust gas is controlled so that the atmosphere of the PM filter is brought into an atmosphere slightly leaner than the stoichiometric air-fuel ratio.

Abstract: An internal combustion engine is provided that performs stoichiometric burn operation under control for providing a stoichiometric air-fuel ratio as basic control for an air-fuel ratio. A particulate filter (PM filter) is provided in an exhaust passage of the engine to trap particulate matter PM contained in exhaust gas. If it is judged that the PM filter will have excessively elevated temperature, fuel cut is prohibited during deceleration. Otherwise, before the prohibition of the fuel cut, the air-fuel ratio of exhaust gas is controlled so that the atmosphere of the PM filter is brought into an atmosphere slightly leaner than the stoichiometric air-fuel ratio.

Abstract: An exhaust passage of an internal combustion engine is provided with an upstream side three-way catalyst capable of purifying exhaust gas and a particulate filter (PM filter) for trapping particulate matter PM contained in exhaust gas. Catalyst warm-up control is exercised for the purpose of warming up mainly the upstream side three-way catalyst at cold start. Filter regeneration control for removing the particulate matter PM accumulating on the particulate filter from the filter is exercised at the cold start after the catalyst warm-up control is exercised.