Thank you so much guys, the only things left for me to think about now, it those injectors and HPFP (High Pressure Fuel Pump) which include fuel pressure regulating valve (of which i have also read other comments as well that are not BMW related for the diesel car that are shutting down while driving) and the problem was a faulty injector.

i hope this link opens, (pity i cant tell what these guys are saying but i could see what they do)

https://www.youtube.com/watch?v=r9jo4uH8S8o&t=524s

(Kia Seronto with fault code P1181) this is what my car is doing.

https://www.youtube.com/watch?v=bzlCDkkeD0U


I shall give a feed back as soon as i come right.