Just got the car back today from a cooling system overhaul. Replaced radiator, all hoses cooling and vacuum, thermostat and thermostat housing, and some other stuff. My fan previously made contact with my radiator and am surprised the radiator did such a good job of putting up with it. Also, my lower radiator hose was nearly punctured by something. And to think, this system survived two days at the track! Everything's fine, but the mech told me that there was something in there that shouldn't have been in the engine compartment. I snapped a picture of it before he threw it out. What on earth is this??? He didn't know what it was for and neither do I. Does anyone have a clue?