[autoart]

I don't know if I'm missing something.
I am on my second fuel pump in the past month.
The fuel psi goes down to 20 psi on hard pulls.
It starts fine within about 4 days. After that, I get a long crank, and stumbles a bit then runs fine.
Could it be anything else like the EKPS or the low-pressure sensor before I change fuel pumps again? 2009 335I. Thanks

[335i54n]

lpfp sensor, ekpm, and fuel reg/filter -check all

[autoart]

What are signs of a lpfp sensor problem?

[iqraceworks]

Originally Posted by autoart

I don't know if I'm missing something.
I am on my second fuel pump in the past month.
The fuel psi goes down to 20 psi on hard pulls.
It starts fine within about 4 days. After that, I get a long crank, and stumbles a bit then runs fine.
Could it be anything else like the EKPS or the low-pressure sensor before I change fuel pumps again? 2009 335I. Thanks

Whats your fuel pressure at idle? If it's around 72psi at idle, and then drops down to 20psi during a pull, something it wrong. Can you post a log showing the LPFP and Rail (HPFP) pressure during a pull?

[335i54n]

lpfp sensor is one of those things that is easier to replace with new than to actually do any testing. Imo doesn't fail often.

[autoart]

From what I have read the lp sensor will stay at the same reading and not move, or throw a code. Mine does neither of those.
I think it's the fuel pump, I ordered a new 1. Will see how it goes

[autoart]

So the problem was I bought a cheap Hella pump instead of the vdo/Continental pump. Once I installed the continental pump, my car was happy again.
I should have known better.

[autoart]

The new lpfp worked for a week then I got low pressure again. I bit the bullet and changed the hpfp and after 2 weeks the pressures have been steady.