This BMW 118i 2-Litre M-Sport was suffering from long cranking, sometimes it took 8 attempts to get it started. Diagnostics showed Error Code 29F3 from Carly diagnostics which pointed to the Low Pressure Fuel Sensor.
This video shows the complete procedure from start to finish including the diagnostics, disassembly, swapping the sensor and reassembly. Although this procedure is for the BMW E81 it is applicable for all BMW models with the Low Pressure Fuel Sensor which includes 1-Series, 3-Series, 5-Series, 6-Series, 7-Series and the X models with fault code 29F3.
I used this sensor: https://amzn.to/3890pHI
Carly Diagnostics: https://amzn.to/2FRlElt