Hi, can anyone help.

I have a crv 2.2cdti that has a lack of power in low gears. Once on the motorway or cruising the turbo picks up ok. I have replaced the turbo and still have no improvement. Before I spend anymore money can anyone shed any light on this. Honda dealers keep telling me its the turbo still but it cant be as i have had it checked and it works fine. Desperate Desperate!!