Idle Stabilization Valve
The idle stabilization valve consists of a small single-wound motor, rotary valve and a return spring attached to the motor's armature. The valve controls idle speed. Varying amounts of DC voltage cause the motor to pull against the return spring.
The amount of current will determine how far the rotary valve is rotated. See Fig 1 . When the rotary valve is rotated, air from the intake air boot to the intake manifold by-pass varies.
The idle stabilization valve receives a voltage signal from the FICU. Variables that effect the amount of voltage received from the FICU are the engine speed, temperature sensor, idle switch, A/C compressor clutch and transmission gear position.
Idle speed is maintained between 650-790 RPM on warm engines and at about 1000 RPM for cold engines. With this system, no idle speed adjustments are necessary or possible. Idle stabilization valve is located between intake air boot and intake manifold.