Mitsubishi Carisma loosing power

hi was driving on moterway and suddenly my car lost power I was near service station so managed to get it parked up no smoke or engine light was oncar seamed ok just sitting in idle when I tried to rev up it struggled to get revs up when I stopped sounded normal sitting at proper revs tried to drive could harly get it moving so I checked fuel filter and it was dirty and looked clogged up so I thought that was the proble so got some1 to look at it and he said thinks its the turbo but I said no smoke coming out car or no engine light on I thought it would be filter but he didn't even look at filter if it was turbo would the car have problems in getting revs would turbo even do that stop it from reving or do you think fuel filter it was glogged and black looked bad cars 70 miles away don't wana go down if its turbo and not just fuel filter thanks for any help