thanks guys,
I will check the engine the next week, this weekend is the birthday party of mu daugther. but answering, the engine rotate by hand smoothtly and you do not feel any contact or friction. I don't know now if the engine have a real problem, let me explain, with the engine started and under load, I cut the fuel rack off, the sound disapear, them, quickly I release the rack and the engine revolutions raise (breaking the inertia) with a heavy injection steram, black smoke and all the other...., during the engine recovering, the sounds increase proportianally to the overinjection, when the engine stabilize, the sound is regular. I think that the knock is normal in the DI engines, what all you think?