System Testing
- Check condition of all hoses and tubes. Disconnect air suction hose from air switching valve. Check that a bubbling noise is heard from air switching valve at idle.
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- Disconnect vacuum hose from air switching valve. Bubbling noise should not be heard from air switching valve at idle. Reconnect vacuum and air suction hoses.
- To check vacuum control valve, race engine and quickly close throttle valve. Check that bubbling noise stops momentarily. If system does not operate as outlined, check each component. See COMPONENT TESTS.