Originally Posted by BMWM.D.
more like a 350i
But yeah, the noise you were hearing is the fuel pump running while the DME was programming. Totally normal. In the future, I'd recommend turning off the daytime running lights (or connecting a battery charger) before flashing the DME. It's best to keep the system voltage in the 14's if you can.
why does the fuel pump need to run when the car is programming? does the DME feed on fuel???