As above, the small black box, just above the turbo inlet pipe, between that and the maf. It is after the 90 degree turn after the maf, has a small bore pipe coming from it.
What is it and what does it do? Is it essential, ie, can i remove it?
Sorry if it is a dumb question!

Thanks.

 

sounds like the resonator box, small pipe from the bottom runs to boost solenoid

 

Best left alone then?