Sportage 3 Diesel consumption ouch…………..???

Hello after 9 weeks Finally my Kia Sportage 3 got back from the workshop!!!! (Blinker completely fail no ECUs Available) 1 day Later the airbag control unit was defective again in the workshop 3 days waiting!!!! Diesel 136 hp Now I was finally on the highway a longer distance driving with speed 140 Needs it to pass 11.7 liters at 120 kmh 9.9 liters!!!! at 100 kmh 8.7 liters…… So fact I don’t get the car below 10.5 liters Through nitt eg al how and what I do. The car is now 1700 Km down so still very fresh but with a statement from the dealer you should first drive 10-15000 Km then Will the engine drive itself can certainly not be in today’s time!!! Did any of you find a similar experience and possibly help???????????? Thank you for your help Greetings