CONTROL METHOD OF DIRECT INJECTION ENGINE

摘要

PROBLEM TO BE SOLVED: To provide a control method of an engine to prevent deterioration of exhaust air emission because of a catalyst not at activating temperature at the time of restarting as wall temperature of a cylinder and temperature of the exhaust air purifying catalyst are lowered during temporary stopping of the engine on a hybrid vehicle assembling a direct injection engine using gasoline as fuel and an electric motor.

SOLUTION: An ECU 7 stops the engine after raising the temperature of the exhaust gas purifying catalyst 5 up to a heat resistance limit of the catalyst by previously changing injection timing of the fuel over to an early stage of a suction process from an intermediate stage of the suction process so that the exhaust air temperature becomes higher in advance of stopping of the engine. Consequently, it is possible to prevent deterioration of emission after restarting because an exhaust air purifying function of the catalyst 5 is displayed after the restarting or in a short period of time after restart since the temperature of the catalyst 5 is high at restarting.

COPYRIGHT: (C)2004,JPO