Hello, ive read this on other posts. Basically my problem is when the engine is under load e.g going up a hill i sometimes get a severe loss of power and black smoke coming out of the exhaust. It also jerks erratically makes it worse if i accelerate more.Its worst around 50mph. Once i get above that speed or on a level road e.g 60 mph it doesnt do it. Fuel consumption is normal. Engine is a DW8 1.9 diesel. Recently changed the air and fuel filter. 06 plate. non turbo. Its a process of elimination to find the fault. Hoping its not the fuel pump does this engine have an egr valve? Could the fuel filter be bad? is one of the hoses split? Any help would be grateful thanks.