Idle Speed/Throttle Actuator - Electronic: Description and Operation

Idle Stabilizer:

Idle Stabilizer Diagram:

The idle stabilizer valve, which is located in the bypass pipe, maintains the appropriate idle speed for various engine operating conditions.

Idle Stabilizer Valve:

The idle stabilizer is a single winding rotary type valve. It consists of a small single winding electric motor, a rotary valve and return spring attached to the motor's armature.
The CIS-E Motronic control unit compares the actual engine speed with programmed speeds for various conditions (A/C on, A/T selector lever in Drive, etc.).
The CIS-E Motronic control unit calculates the amount of time the motor winding is energized (duty cycle %), working against the return spring. The amount of bypass air and the idle speed is determined by the position of the rotary valve in the idle stabilizer.