Ford Ruckles at lower load range during acceleration

Hello we have been having problems with our Ford Transit 2012 2.2 Diesel 125hp FWD for months now. The engine is an AT engine from Ford with now almost 15,000KM. It’s only the engine new, not all attachments. For about 3 months we have been in the lower load range to give in to the gas. If then you don’t give any more gas it shrugs like this. You also hear a sucking noise from the engine compartment when it jerks… It’s like if you would tap on the accelerator quickly and only briefly. Ollgas it is completely gone. The AGR is new, but I still know if they have cleaned everything, but the engine is new. I drive almost only Premium Diesel. Another problem is that the car starts cold 1A and very clean, as soon as it is warm it is bumpy up to the point that it does not start at all and needs a new attempt. Twice the engine just went out in idle. We were already in some workshops but none has solved the problem, a master said it clearly But I don’t know what to do without a fault in the system. LMM is also new. Coupling and ZMS too, is not important but is new Diesel filter is also new. I am really a bit perplexed. We have no exhaust smoke and the injectors are perfect according to a Ford workshop. Does anyone have an idea or the same problem? I would be very grateful because I don’t want to run into the next workshop where the next part is exchanged.