Anti-Afterburn Valve

1. Run engine until normal operating temperature is reached and continue to run at idle.
2. Disconnect hose between air control valve and air pump at the air pump end.
3. Place a finger over disconnected air hose and ensure air is not drawn into hose with engine running at idle.
4. Accelerate engine above 3000 RPM, then quickly decrease engine speed. Air should be drawn into hose for several seconds while decelerating.
5. Replace valve if operation is not as described.