Help, Fiat Punto 188 60 HP gasoline trucking like a tractor

Hello, I hope you can help me and calm me down! My car was now in 2 workshops that find no mistake. Description: It started the problem that he suddenly took no gas while driving from the 3rd to the 2nd or the 1th in the 2nd aisle (he jerked, stalled, and then drove again, as always) The next 2 weeks everything was totally normal again. Suddenly, he toured at the cold start to 3500 and needed about 2 minutes until he reached the usual 1000 w ar. While I thought the car was flying apart, he jerked like a tractor and made the worst noises like a tractor – I could have made a milk shake. During the car ride everything was ok again (no gas problems, no jerking – nothing. Drive into the workshop – problem explained – error diagnosis without result – black spark plugs were replaced. The next day same problem as described above, only that it had to be started 2 times (since immediately – wi In addition, BUT came another problem and that at every traffic light: clutch came, gas was to be heard – he wanted to drive – could not (as if the car were held from behind) only with high speed about 3000 and after several attempts I could continue driving – but this without unusual noises or problems. Now my car came back to the workshop, no error received via error diagnosis. Supposedly the workshop of another Punto, the throttle valve, ignition coil and Zü ndkabel exchanged – result: same problems. Head seal is fine, oil and fuel is also :-). Lambda probe and air mass sensor, says the workshop, would be indicated by a fault diagnosis. Should it not be. What has my car? Please help me. My Punti no longer has so many components or? Thank you Thank you! LG Claudia