loose valve?

[Monks562]

Hello I'm a first time owner of a 94 camaro and I gotta say its one hell of a car. I got my car from a tow yard for very cheap but it runs pretty good and doesn't grind. It's quite the fixer upper. The previews owner did somethings that makes you scratch your head and wonder what he was thinking like hooking up an amp put not putting the screws back on the panels he removed....But that isn't my problem atm My problem is this valve I have no idea where it goes? I was gonna remove my radiator to see if i can find something but I'm waiting to get paid so i can change the coolant,spark plugs,and change my oil just wanted to get some info on it before I start messing around and hopefully just go straight for the fix. Thanks in advance for any help and sorry if i posted in the wrong section any pics and or links are greatly appreciated.