System Testing

Check condition of all hoses and tubes. Disconnect air suction hose from air cleaner. Check that AS valve is making a bubbling noise from the AS hose at idle.

Fig 1: Air Suction System (Pickup)
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Disconnect vacuum hose from the reed valve. Check that a bubbling noise is not heard from the AS hose at idle. Reconnect vacuum hoses.
To check vacuum control valve, race engine and quickly close throttle valve. Check that bubbling noise stops momentarily.

Fig 2: Testing Vacuum Control Valve