What is this engine part?
 

What is the black box forward of the coolant reservoir, and it has the black pipe running to it, round the power steering reservoir?

My pipe into it is all split, where the pipe has the folded edges (can't think how else to describe it!) below and right of the power steering reservoir.

ECU housing box

The pipe is just to cool it somewhat!

ok, no need to worry then !

As above, that's where the ECU lives. The crinkly flexible part of the air hose was damaged on mine too, however I'm keen that the ECU is kept cool, so while I haven't sourced a replacement I did tape it up a bit to help the cool air get to where it's supposed to. I'm thinking that the cooling pipe was put there for a reason by Volvo, so should be kept operational?

thanks, I will do that too