Air Injection: Description and Operation

CIRCUIT DESCRIPTION






To accelerate the activation of catalyst when warming up the engine, the air injection system pumps the secondary air to the exhaust manifold. The secondary air is supplied by the air pump and it is pumped to the exhaust manifold through the air switching valve. Open and close movement of the air switching valve is regulated by the vacuum switching valve (VSV).The air pump and the air switching valve are observed by the ECM and are used to detect malfunction in this system.

The ECM monitors the secondary air injection system and detects malfunction using a pressure sensor located on the air switching valve.