Nissan Navaro D22 51 Plate Fuel Problem?

I have a nissan D22 with what would appear to be a fuel problem when you get to approx 50mph the vehicle starts to pull back as if if is being starved of fuel if you then carry on and try and increase the speed it will get worse and then white smoke will come out of the exhaust and vehicle will slow down as if it is about to cut out. I have been told by nissan that they think it is a fuel filter problem and that i should replace the filters can any body tell me if they aggree and also how many filter are there I am led to belive that there may be a filter on the fuel pump that can come out like a little microfine filter as well as the one in the engine bay and also a pre filter thats in line is this correct