Mercury - Distributor Sensor Ignition Component Composite & Stainless Steel 892150Q02. Overview. There's a certain confidence that comes from knowing your engine will fire up cleanly every time - especially when you've got a full day on the water ahead of you. The Mercury 892150Q02 Distributor Sensor brings that peace of mind to MerCruiser engines running Thunderbolt ignition systems. It's one of those parts that works quietly in the background, making every start smoother and every idle steadie