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Idle Up Control Valve: Description and Operation

Idle Speed Control (ISC) System:






The Accelerated Warm-Up System (AWS) Solenoid Valve, located on the intake manifold, acts to ensure good driveability and low emissions immediately after engine start under specified conditions. The valve is a component of the idle speed control (ISC) system.

The valve is ECU activated under these conditions:

1. Coolant temperature between 59° - 95°F (15° - 35°C).
2. For 17 seconds after engine start, at idle only.