Digifant I

1. Check the function of the Auxiliary Air Regulator by checking its effect on engine idle speed under various conditions. When the engine is cold, engine coolant temperature below:

86°F (30°C)

2. Disconnect the Auxiliary Air Regulator harness connector. START the engine and pinch shut either hose connected to the Auxiliary Air Regulator to the intake manifold. The air passage should be open and the engine should lose rpm and possibly stall.
3. When the engine is fully warm, with the harness connector attached, pinch shut either hose to the Auxiliary Air Regulator as before. The air passage should be closed and engine rpm should not change.
4. The Auxiliary Air Regulator can also be visually inspected in place using a light and a small mirror. When the air passage is open (cold engine), it should be possible to see light through air passage. When the air passage is closed (warm engine), it should not be possible to see through the air passage.
5. If the air passage remains open when the engine is warm, check to see that the Auxiliary Air Regulator is receiving voltage at the harness connector. There should be battery voltage (approximately 12 VDC) at the connector any time the ignition switch is turned ON. If no voltage is present, check for faulty wiring.