hi folks, got a problem with my sedona crdi 05. see if any of you can pin point the problem. had injectors replaced with refurbished ones, and had to change pressure pump also, but at 2500rpm and about 75 mph it starts hesitating and when i put my foot down it rattles and smokes badish. until i drop under 75mph. any suggestions, my thought was a new injectors is breaking down under load, ?? cheers for any input.