05 xc70 going limp

[Moosexc70]

Hello all,
I'm new to this forum and was wondering if anyone could help me. I have a 05 xc70 d5 awd with 120k on the clock. Amazing car runs smooth ( well did ) and has not let me down for the 3000 miles o have put on it since owning it. But the other day when overtaking it went limp and the dreaded red triangle came up saying Engine system service urgent. It went so limp I could not get the revs past 2000. I stopped and started her back up and away she went fine until again I put the foot down slightly to over take and the same happened. It runs fine if I keep her nice and chilled but if I need a bit more power it just goes straight back in to limp. In old boy at my work who has only ever driven D5's says it will be the fuel filter. Do the experts here agree?

Any help would be great

Thanks in advance