Fuel System Pressure Release
Fuel system pressure release procedure is not available from manufacturer. It may be possible to remove fuel pump relay, start engine, and run engine until fuel pressure drops (engine stalls).
On 535i the fuel pump relay is located on right rear corner of engine compartment, next to DME control unit and DME master relay. First relay (viewed from top to bottom) is Digital Motor Electronics (DME) master relay, followed by fuel pump relay and then oxygen sensor heater relay.