Operation CHARM: Car repair manuals for everyone.

Idle Control System


The curb and fast idle speeds of the engine are controlled by the electronic air control valve, in response to various signal inputs within the system (A/C signal, Starter signal, etc.
Electronic Air Control Valve (EACV)
The EACV changes the amount of air bypassing into the intake manifold in response to electrical signals sent from the ECU. When the valve is activated, it opens to maintain proper idle speed. After the engine is started, the amount of air is increased to raise the idle speed accordingly. When coolant temperature is low, the amount of bypassed air is directly proportional to coolant temperature.