[94vg30de]

Background:
Recently changed sending unit assembly due to leaking plastic on top, and Fuel Vapor Detection Pump "Leak Diagnostic Pump" because I thought that it was causing the code for the air leak.

Symptom:
After replacements, leak is gone, fuel smell is gone, no codes for leak, but now I have intermittent stumble at idle. Happens hot or cold, full tank or mostly empty.

Hypothesis:
I've searched, but on the N52 there are 3 hoses from the sending unit that go to the top of the fuel pump:
1. snap connector, black
2. open hose, black
3. open hose, white/clear

2 and 3 appear to be interchangeable positions, but does it matter which connection go to which port? The fuel pump (passenger side) seemed to be open holes on top, so I don't understand why it would matter which hose went where.

Alternatively, did I introduce a bubble into the system somehow by opening the fuel line? How do I bleed that out?

[NZE90]

What brand of parts did you use?

[94vg30de]

FCP Euro source for VDO
https://www.fcpeuro.com/products/bmw...ft-16117163295

[94vg30de]

[SOLVED]
Opened fuel pump and swapped black and white corrugated hoses, re-primed, car runs great.

Calling this solved unless it comes back

[94vg30de]

[UPDATE]
Unsolved, problem came back within one drive of swapping hoses, still under investigation.

Current suspicion is coil packs, which are on order