[Motocorditoru]

Hello, i bought recently a car and i drove it aprox. 20.000km. After this period, sometimes, especially when i drive in city, i get the error drivetrain. Tommorrow im going to put ista and see the error code, but when i bought it, the mechanic told me that in clutch C, i have 750.0bar and 33ms on rapid fill times. When i drive in the city and i brake, i feel like something isnt smooth when it is changed to 3rd gear
What should be the problem?

edit: i put ISTA on it, it show the error 420341 - gear ratio monitoring: geershift 4 to x not plausible