Mazda Motor Corporation

Takeshi Yoshimura

Nobuhiro Hayama

Shigeo Kato

Yoshitaka Tanikawa

Toru Nakanishi

Mutsuro Sameshima

An engine intake system including a primary and secondary intake passages which are separated from each other and are respectively provided with a primary and a secondary fuel injection valve. The secondary intake passage is closed and the secondary fuel injection valve is inoperable for light load engine operation. When the secondary fuel injection valve is restarted to operate for heavy load engine operation, the quantity of fuel supply is momentarily increased to avoid any stepwise change in the engine output torque. The amount of the increase in the fuel supply is increased in response to a decrease in the engine speed. When operation of the secondary fuel injection valve is stopped, the fuel supply is decreased.

Fuel injection control means for internal combustion engines

An exhaust purifying system for an automobile engine including an exhaust system for the emission of exhaust gases to the atmosphere through a catalytic converter. The system comprises a temperature detector for detecting a signal indicative of the temperature of the catalyst, a total engine operating hour detector for detecting a signal indicative of the total operating hour over which the engine has been operated, a spark timing control for retarding the spark timing when the temperature detector detects that the catalyst temperature is lower than a predetermined value, and a retard time corrector for increasing the amount of control to be performed by the spark timing control with increase within a predetermined range detected by the total engine operating hour detector.

Growing community of inventors

Higashihiroshima, Japan

Takeshi Yoshimura