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Home >> Audi >> 1988 >> 80 Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> BOSCH Cis MOTRONIC System >> Operation >> Ecu Controlled Components >> Idle Stabilization Valve
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Idle Stabilization Valve

Idle stabilization valve consists of a rotary valve and a return spring attached to an armature. Valve controls idle speed. Varying amounts of DC voltage sent by ECU cause motor to pull against return spring allowing air to by-pass throttle plate.

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.