Inspect Intake Air Control Valve Operation

Start the engine.
While the engine is idling, check that the actuator rod moves. See Fig 1.

Fig 1: Checking Actuator Rod Movement
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Disconnect the VSV connector, and check that the actuator rod returns. See Fig 2. If operation is not as specified, inspect the intake air control valve, VSV and ECM.

Fig 2: Checking Actuator Rod Return Movement