Secondary air supplying device of an internal combustion engine

摘要

Disclosed is a secondary air supplying device of an internal combustion engine having an exhaust passage provided with a catalyzer for purifying exhaust gas. The device includes a first air injection port provided in the exhaust passage at the upstream side of an exhaust manifold and a second air injection port provided in the exhaust passage at the upstream side of the catalyzer. Under the engine warming operating condition only when the engine speed is abruptly accelerated, or during a predetermined time interval after the engine is warmed, is secondary air injected into the exhaust passage from the second air injection port. When the engine is in the other operating conditions, secondary air is injected into the exhaust passage from the first air injection port.