POLL: How many times have you replaced your fuel pressure sensors

How many times have you replaced your fuel pressure sensors? (Choose one for low and one for high)

  • Low Pressure Sensor: never

  • Low Pressure Sensor: once

  • Low Pressure Sensor: twice

  • Low Pressure Sensor: 3+ times

  • High Pressure Sensor: never

  • High Pressure Sensor: once

  • High Pressure Sensor: twice

  • High Pressure Sensor: 3+ times


Results are only viewable after voting.

veer90

Lieutenant
Nov 16, 2016
1,000
774
0
West Nyack, NY
Ride
e90 335i 6MT
There was no real issues with either of my sensors.

Low pressure sensor was replaced in an attempt to get warrantied HPFP which the dealer ended up denying anyways.

High pressure sensor was done as preventative maintenance one time when I had to remove the fuel rail.
 
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matreyia

Major
Apr 19, 2017
1,780
711
0
Ride
335i e93
Looks like that individual is a punk based on the poll. I haven't changed mine either.

Yes, he be a punk... with an ultrasmooth running fuel system, Precision Raceworks stage 3 LPFP with port injection using the BPM4 Controller.
 

GreyNBlueE92

Sergeant
Oct 3, 2018
266
92
0
27
OH
Ride
2007 E92 335i
Only reason I had to replace mine is because I broke the plug the first time I tried to remove the intake manifold. Replaced the whole line with the updated part. It has a rubber insert instead of a solid mount. Mine is a 2007.
 

JimboFresh206

Sergeant
Jan 29, 2018
289
152
0
Ride
335/635/535/533/633
99k on low pressure sensor from 2007....

my LPFP reading stays at 88-90 psi for a few mintues, even after the hobbs is closed on the second pump, is that normal?
 

doublespaces

Administrator
Oct 18, 2016
9,303
4,332
0
AZ
Ride
2009 E93 335i
I changed my LPFP sensor and voltage regulator at the same time. Since then, I started to notice my low pressure dipping during pulls recently and I don't recall that before, reading more accurately maybe? I also had a change to my tune around that time so there are various factors involved. Low pressure was always really spikey, bounced around a ton and my hpfp was throwing a 29f2 code in some conditions, caused my hpfp to just quit and go into limp. I have put very limited miles on the car since then but the code hasn't came back yet. Seeing my low pressure dipping is a relief because it tells me my pump is going bad, was bad or just not able to keep up in general so it must be faulty. I finally have something to point to that might actually make sense. It is sort of irritating because I was under the impression that my LPFP has been fine this whole time and have been replacing everything else under the sun.

I've got a feeling that 'decent' low pressure readings aren't indicative of a healthy lpfp. I have no proof but I want to believe the DME is compensating something else in order to fit 'inside' the other parameters and might make the low pressure look better than it really is.

The old '50 psi and above' adage, I think we should probably toss that out.
 

Jeffman

Major
Jan 7, 2017
1,620
1
629
0
Low pressure was always really spikey, bounced around a ton...
Did you also get 2AAF codes? That’s the code I always get within a minute after clearing codes. I’m curious who else gets 2AAF? I was hoping the BMF4 would “solve” the underlying issue(s) giving rise to 2AAF. But maybe it’s my LPFP sensor, which I plan to change this weekend with the upgraded “silver” OE one from Bosch ($39 on Amazon).
 

iminhell1

Sergeant
Jun 17, 2018
419
207
0
I did the low sensor because I had a some free money from FCP to spend.

Didn't change anything I can attest to. Apart form my fuel gauge now not reading quite correct.


Have not done High.
I hate this fuel system so much I will avoid doing any more work with it.



And FWIW my setup is this,

1 450 low pressure as my main pump. Just sitting in the bucket, not tied down.
1 450 high pressure ziptied to the inside of the bucket
PR wiring, vacuum comes from the muffler flap
Fuel It line upgrade.
Reman HPFP
index 11's
 
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GreyNBlueE92

Sergeant
Oct 3, 2018
266
92
0
27
OH
Ride
2007 E92 335i
Didn't change anything I can attest to. Apart form my fuel gauge now not reading quite correct.

And FWIW my setup is this,

1 450 low pressure as my main pump. Just sitting in the bucket, not tied down.
1 450 high pressure ziptied to the inside of the bucket
PR wiring, vacuum comes from the muffler flap
Fuel It line upgrade.
Reman HPFP
index 11's

When putting your pump back in, try and make sure all the fuel lines are on the other side of the bucket that the fuel level sensor is on. Mine was off, reading about 3/4 when full, until the last time I put it together like above. It's kind of hard to get it all to fit so I use a long screwdriver to help. Zip ties ftw
 
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doublespaces

Administrator
Oct 18, 2016
9,303
4,332
0
AZ
Ride
2009 E93 335i
Did you also get 2AAF codes? That’s the code I always get within a minute after clearing codes. I’m curious who else gets 2AAF? I was hoping the BMF4 would “solve” the underlying issue(s) giving rise to 2AAF. But maybe it’s my LPFP sensor, which I plan to change this weekend with the upgraded “silver” OE one from Bosch ($39 on Amazon).

I've always gotten the 2AAF code with an upgraded pump, I thought everyone did? I've read on multiple occassions to ignore it, but would be interested to know if people have resolved it somehow.
 

matreyia

Major
Apr 19, 2017
1,780
711
0
Ride
335i e93
I've always gotten the 2AAF code with an upgraded pump, I thought everyone did? I've read on multiple occassions to ignore it, but would be interested to know if people have resolved it somehow.

Ever since I install the upgraded controller, I have never had that code pop up ever again. Mind you, I have new low pressure and high pressure sensors.
 

RSL

Lieutenant
Aug 11, 2017
937
501
0
I've always gotten the 2AAF code with an upgraded pump, I thought everyone did? I've read on multiple occassions to ignore it, but would be interested to know if people have resolved it somehow.
Tune related 2AAF are an easy fix (at least on stock fuel system with single upgraded pump) once some tables are defined. Maybe they'll make it out with HPFP tables.

Amb pressure to smooth because everything else put rail and LPFP on top of each other. Code depends if LP min/max values exceed thresholds or not, can have large moves and still stay below.

Typical tuned mess, can be 2AAF all day:
lpfp_tune_nopid.png


Tuned (different) with LP adjustments, 2AAF never:
lpfp_tune_pid.png
 
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Jeffman

Major
Jan 7, 2017
1,620
1
629
0
Assuming the LPFP pressure swings are real, I think it would be ideal if there is a way to tune the DME to minimize the pressure swings. But if 2aaf is just an annoying notification which has no real affect on anything then widening the pressure thresholds when the code is thrown will helped to distinguish whether there is a real problem or not.