Your problem is the siphon jet is not doing it's job. In the VAST majority of this case, the o-ring to the siphon jet I have a very detailed thread on how to fix that problem for free.

You can confirm the siphon jet is not working by unlocking the hidden dash (google how) and display test 6; it will show the fuel level in liters on each side of the tank. The right side should show about 1.5L of fuel always once the total is less than 27L. if the right side ever drops below 1.0L, your siphon jet is not doing its job. (almost always a leaky o-ring but also end-of-life electric pump won't make enough pressure to supply the engine AND the siphon jet; it's very rare for that to be the case; almost everybody that replaces the electric motor when the siphon jet is not working will fix/replace the siphon jet after because it wasn't the motor pump.

search for my thread about siphon jet and the detailed fuel system and read that one first to learn how the fuel system works on the X5.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)