Air Switching Valve

With engine running, apply vacuum to valve. Air should be injected upstream only. If air escapes from silencer ports or is applied both upstream and downstream, valve is faulty and must be replaced.

To check vacuum supply system, observe engine vacuum at idle with engine cold. Vacuum should be present until engine reaches normal operating temperature. With engine warm, vacuum should only be present for a limited time after engine starts. See Chrysler Electronic Ignition Systems.