Power Loss - TDI PD115, Engine code ATJ

[jojo]

Hi guys, whilst driving back to Solihull from Stratford along the A34, the car suddenly lost all power, very similar to 'limp' mode. So I pulled over to switch car off and back on to see if it would reset itself and cure the problem. Unfortunately that was no joy, but there was no warnings on the dash neither, so I carried on my journey @30mph with what felt like n/a power and a whole load of black smoke coming out the back.
Once I got home, I popped the bonnet open and blipped the throttle, and there was a loud hissing/blowing noise coming from the front end passenger side, I take it thats the intercooler hidden down there? Sounds like it's blowing or there's a loose hose, anyone else experienced the same problem?
The car has done 166k miles and is regularly serviced, I have changed the MAF twice and the temp sensor once in the last 7 years of ownership.