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Idle Up Control Valve: Description and Operation

Idle Speed Control (ISC) System:






The Accelerated Warm-Up System (AWS) and Air Supply Valve (ASV) Solenoid Valves, both located on the intake manifold, act in conjunction to ensure good driveability and low emissions immediately after engine start under specified conditions. These are components of the idle speed control (ISC) system.

Both valves are 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.