Anti-Afterburn Valve

With suction hose remove from valve and engine running at idle, hold hand over opening of suction hose. If strong suction is felt, valve should be replaced. Run engine at 3500-3800 RPM and then close throttle suddenly. Air should be sucked into the hose for between 0.2 - 1.0 seconds. Run engine at idle and remove wire going to solenoid of anti-afterburn valve. Make sure that air continues to be sucked in through air suction hose while wire is disconnected from solenoid.