Originally Posted by 843de

I pop the hood daily because its a pilot thing, once you've had pre-flight checks ingrained in you, you just find yourself doing them on everything. I think a once a week look under the hood is about right for the average driver. As for where the coolant went, maybe it didn't go anywhere. Depending on the engine temp when you checked it in October and the other day, the level in the recovery tank might have been different. If you're not smelling it inside or outside the leak if any is small to insignificant. Also, even though the cooling system is "sealed" to a point, some coolant loss will occur over time, just have to check periodically.