Found out why I had a lack of power. It was a split in the egr to intercooler hose. My local stealer was wanting £75 plus VAT. I got a silicone one from Derby Performance Hose, plus the 2 uprated hose clamps for under £30 delivered.
http://www.dphsiliconehose.co.uk/ind...product_id=245
I reckon the split has been like that since I got the car and has just kept getting worse as I've drove it as it's never felt as quick as it does now & my MPG is a lot better too.