Idle Speed/Throttle Actuator - Electronic: Description and Operation

Idle Valve:

PURPOSE
The idle air valve maintains proper idle speed under the various engine load conditions.

CONSTRUCTION
The idle control valve consists of two opposed windings, an armature, and a rotary slide.

OPERATION
The electronic control unit regulates idle speed by controlling the amount of time each winding is energized. The amount of bypass air is determined by the position of the rotary slide.

The electronic control unit compares actual engine speed with programmed speed. By varying the time each winding is energized, the opposing forces on the armature cause it to take a fixed position, allowing the correct amount of bypass air to maintain the correct idle speed.