Golf mk5 TDi 105 no boost

Hi guys,

I know im in the wrong forum, but VW and Skoda share the same engine.

I have a mk5 Golf TDi 105 and it litrally has no boost, its been standing about a month, but before hand ran absolutely fine, I took it out the other day to charge battery and I struggled to get it over 50 mph!

the faults that have come up are

Engine coolant temp sensor on radiator outlet G83 Signal to high P2185

Manifold Pressure Boost Sensor G31 Signal to high P0238

Boost Pressure sensor implausible Correlation P1592 

Any ideas chaps?