450 gears/switching test

moinsens, the following problem: after engine change, the gearbox switches only up to 2nd gear, after inserting it into the third knarrt as if the coupling does not separate correctly, in automatic mode come immediately after switching attempt into the third the three bars in the display. restart is immediately possible. it is a cdi, bj. 2003, 450 cabrio, running power 220tsdkm, dispenser motor comes from nem 2000 cdi with 150tsdkm. gear oil has already changed, was black and smells burned. my question, can it lie on the clutch disc? it switches through 2 lanes and backward gear cleanly. must ask tomorrow if the clutch disc has remained on the motor, in addition my question, are the discs identical or has there been a change? thank you for your answer.