Originally Posted by DanW@FastFord

100% split boost hose. 90% it'll be the hose that runs between the intercooler and the EGR valve on the front left of the engine. DON'T buy one from Ford, They're up to £90 and will go again. Get one of the silicone ones off Ebay instead. Fairly straightforward DIY job, if a little fiddly. Use some washing up liquid to help get the new hose on.