Check testing equipment for leaks!
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2005 BMW 745i, 2005 BMW 745Li, 2004 BMW 745i, 2004 BMW 745Li, and 2003 BMW 745i. However, it is still accessible from the selected car via links, so may be relevant.
Select "Measurement" function on Diagnosis and Information System (DIS).
Increase pressure by 0.2 bar with pressure regulator on special tool 16 1 171.
Using special tool 13 3 010, disconnect delivery line from special tool 16 1 171 to fuel filler neck.
Wait 60 secs.
Read off final pressure value and compare with starting pressure value.