Changed my oil this morning in its regular 6k change and also changed the fuel filter for the first time.....
I think the BMW schedule is 60k or more for the fuel filter, but I read it should be done more regularly.
Here is the state of the old filter.....shocking. Covered in brown sticky residue. It should be white! I can imagine this will cause a pressure drop enough to affect performance.
Will test drive and report back.
If you have not done yours then you need to. I think every 2 years or 20k they should be changed.