I have done a ton of work, including installing turbo on my 2001 miata. I am now hunting vacuum leaks. In the process this morning I found this piece sitting on the right fender well. Where did it come from? Any help appreciated.

P.s. I already know where the key came from...

 

I've completely torn apart 10+ miatas and I do not recognize that hardware at all. The only thing that is remotely similar is the pin that holds the door hinge to the chassis.

 

Is that the PCV plunger? Can't be?

That would be a pretty bad vac leak lol

 

As I was hunting leaks, I tried to pull out the (original) PCV valve. It broke and piece flew out. That one was not found until now. Thanks!