Air Injection Bypass Valve: Description and Operation

Electric Air Control Bypass Valve With Solenoid De-energized:

Air Injection Control:

PURPOSE
The electric air control valve combines electronic control with the normal bypass valve function. This valve can be electronically controlled to provide bypass air under any driving mode.

When the solenoid is energized, the valve will perform like a standardized bypass valve. Air from the air pump is directed to the exhaust ports, unless there is a great sudden rise in manifold vacuum due to throttle deceleration.

When the solenoid is de-energized, the pressurized air from the air pump is allowed to enter the decel timing chamber. This places sufficient pressure on the metering valve diaphragm to overcome spring tension, closing the valve, causing air to bypass to the atmosphere (silencer).

At higher engine speeds, excess air is exhausted to the atmosphere (silencer) through the pressure relief valve.


OPERATION
When grounded by the ECM, the solenoid causes the valve to direct air to the exhaust ports. When de-energized air bypass to the atmosphere, air will go to the ports provided the valve has a ground to the ECM and good manifold vacuum.