Sierra Cosworth Motor

Hello, I have a Cosworth Sierra engine and when trying to start it it is revolutionized and almost starts but begins to make black smoke and drown. When the distributor moves or explosions for the admission collector or the escape, and I can't know what he has. Could it be the turbo that does not turn well and drown the engine, or will it be the repair of crankshaft shells, which makes the engine hard and fails to start, do I amount to the car and start it pushing? All the best.