Got it fixed at last.
Changed the intake manifold because i did not like where the vacuums for the LPG were on the previous one, plus i had the idea that the flaps(that are not visible) didn't function, there was a little improvement, but still, no power cold and till 3000rpm.
Then it came out to be the TPS in the throttle body, it showed values not in specification at all, after contact spray was applied it became a little better, then 50km after the car started to loose rpm on idle and shut down. New throttle body and all is ok now, still after reset of KAMs the Short fuel trim stays in +32.81% , but the car runs fine. Still to investigate what the problem with the short fuel trim 2 is. It was strange with the TPS, because it was checked and it was ok when the car started to do the problems, but who knows.