Does anyone know where it goes?

 

I don't know offhand, helpful to post what car you have. But look here realoem.com and you will probably find it pretty quick.

 

I have no idea what model car you have but it looks to me like a 'growl' tube. It would connect from somewhere on the intake to the firewall and would enhance the sound of the engine for the benefit of the occupants inside the car. It's one of the stupidest things I've ever seen an auto manufacturer do. It was the first thing I removed from my last car which was a FR-S.

 

year 2008 r56 mini s , couldn't find anything on realoem.com.

 

getting high emissions warning