Air Control Valve: Inspection

TURN AIR CONDITIONING SWITCH OFF
CHECK IDLE-UP
1. Start the engine and run it at idle.
2. Fully turn the steering wheel.
3. Check that the engine speeds decreases when the vacuum hose of the air control valve is pinched.
4. Check that the engine speeds increases when the hose is released.
  
  Fig 1: Identifying Vacuum Hose
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