Hi can anyone help me I have a year 2000 2.8td fiat based motorhome & have lost a lot of power , very slow on the pickup & will not rev right out can not get over 60 mph on the flat & if any sort of incline it will not pull in 5th gear I have to drop to 4th & max speed 50 mph its like the turbo is not working, its nice & smooth there is no strange noises from the engine but when stopped & out of gear engine revs fine till about 3000 rpm then seams to misfire & puff black smoke