So my problem was adjusting the rebound damp, I always thought that I had to adjust it with the ETA knob, but I just realize that I was wrong because the rebound adjustment its on the right leg and when I turn the adjuster its feels endless and it doesnt make any difference, the fork its a marzocchi Z1 FR QR20 year 2004 and I bought it with a used bike, the bike works great and thats the only problem that I`m having, and it sucks because there`s no a marzocchi service in town, not even in the country hehe anyways thanks guys