Control of Fast Idle For Cold Engine Operation

Air Regulator:

PURPOSE
Provides fast idle when the engine is cold.

LOCATION
On the Idle Air Adjusting Unit, at the back of the intake manifold.

OPERATION
The intake collector mounted air regulator is used to provide a cold fast idle. Cooling system fluid circulates through the air regulator, warming a wax pellet. When coolant temperature is low, opposing spring pressure forces the piston back. With the piston retracted air is allowed to bypass the throttle plate to achieve a faster cold idle. As coolant temperature rises the was begins to expand, closing the bypass passage and returning the idle to normal curb speed.