My first idea was the Railpressuresensor-Plug at back site of the machine. This Plug is the reason of uncontinous running at 2000-3500 rpm (120-170 km/h). In last year I starting my machine, runs 2-3 seconds and stopps. No starting more at this moment was possible. The BMW-Servicemobil comes and found the error: RP-Sensor-Plug. Now I buy an "Adaptercableset" (in German "Adapterkabelsatz") and I hope, the error is killed with this part
If you do not know, whether the "Adaptercableset" was inserted at Your Car, You can see it on back site of the machine. If You find an back-bound plug and another plug with cable to the BlackBox in the left site (seen from front), the Railpressure-Plug is replaced. If this plug not replaced, You can smile.
If not, then the endless search is beginning :( I hope, You can smile.