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Auxiliary Air Regulator

  1. Disconnect hoses from auxiliary air regulator. Use mirror and small flashlight to inspect valve opening. See Fig 1 . At room temperature, valve should be slightly open. Valve should close within 5 minutes after cold engine starts.
  2. If valve does not operate properly, check for power at connector with engine running. Connect test lamp across connector terminals. If lamp does not light, check fuse and wiring.
  3. If lamp lights, check resistance of auxiliary air regulator. If no resistance is measured, regulator is defective. Ensure electrical connections are tight and terminals are clean, prior to measuring resistance.
Fig 1: Checking Auxiliary Air Regulator Operation Valve should close after engine is running for 5 minutes.
G35414