Mercury - Idle Air Control Valve MPI Series Airflow Management Precision-Machined Metal 8M0181068. Overview. Any boater who's spent time around a MerCruiser engine knows how comforting a smooth, steady idle can be. When the water is calm and the dock is just ahead, you want your engine to respond with quiet confidence-no hunting, no stumbling, no surprises. That's the kind of reliability this Mercury Marine part delivers. The 8M0181068 Idle Air Control Valve helps your engine breathe exactly the