I have a rip in a hose, that I believe to be the PCV hose of my MK1 Ford Focus.

The hose is behind theintake manifold (?) and is part of a T-shaped hose arrangement that goes down in to the engine. There appears to be a metal junction at the cross that connects all three pieces of hose making up the T together.

As I only have a rip in the upper left hand part of the T (hope that makes sense?) can anyone tell me if I can just buy that piece of hose and replace or do I have to buy the whole arrangement and replace (which looks a far trickier job than just replacing the piece of hose that's split). Also, what do I ask for when I go to the dealer/look on Ebay?

Can I just buy something like this (making sure I get the right size diameter of course)?:

http://www.ebay.co.uk/itm/BLUE-SILIC...5e838ce&_uhb=1


Finally, my car has a very fast idle. I am presuming this hose is part of the vacuum system and could be the cause of this fast idle, does that sound right?

Cheers

Andy