[neilvosko]

i have the sensor for sale to resolve the p29f3 code

[themyst]

I got the 29F3 code too, but I am wondering if it's possible to replace the sensor without pulling the intake manifold.

[neilvosko]

it is possible....there is a junction box in way with latches and you may struggle a bit with it....just remove the dci.

[neilvosko]

try to use screwdrivers and long hemostats to do it

[07tundra]

Originally Posted by themyst

I got the 29F3 code too, but I am wondering if it's possible to replace the sensor without pulling the intake manifold.

Yes it takes about 20-30 min taking your time! I did mine very simple to do

[themyst]

wondering what this sensor does in terms of fuel regulation, car seems to operate normally with no codes except for the persistent 29F3.

but I am getting this weird WOT onset timing drop which magically ONLY happens as meth turns on. wonder if this sensor would be the cause.

[bimmertt]

Originally Posted by neilvosko

it is possible....there is a junction box in way with latches and you may struggle a bit with it....just remove the dci.

The junction box was a PITA to remove. After 30 min of trying to remove it by hand, I decided it was worth it to ruin one of my flat heads like the DIY mentioned.

[neilvosko]

the latches are opposite of your direction and on bottom of box.....more PITA.

[Jklad]

Is there a way to accurately test if the lpfs is starting to fail, prior to getting a code? Eg with a Cobb tune?

[Indo Rider]

Originally Posted by themyst

wondering what this sensor does in terms of fuel regulation, car seems to operate normally with no codes except for the persistent 29F3.

but I am getting this weird WOT onset timing drop which magically ONLY happens as meth turns on. wonder if this sensor would be the cause.

Holy shit! I have the exact same thing. I thought it was related to all the changes I've been making with adding the BMS backend flash and new JB4 firmware or some combination of those and various settings, but it just started happening around the same time this code showed up. I have new sensor on order. Wonder if you're on to something here...

[themyst]

Originally Posted by Indo Rider

Holy shit! I have the exact same thing. I thought it was related to all the changes I've been making with adding the BMS backend flash and new JB4 fireware or some combination of those and various settings, but it just started happening around the same time this code showed up. I have new sensor on order. Wonder if you're on to something here...

probably because if the sensor went to shit, the car cant properly regulate fuel on the LP side. just a wild guess lol.

also no matter how much fuel I pull my trims go retarded negative. my open loop is down to 40 and my trims go negative.

im probably just gonna dealer it since I got two bum vanos solenoids as well. thank god for CPO lol.

[Indo Rider]

Originally Posted by themyst

my open loop is down to 40 and my trims go negative.

Wow, me too! I even cut my meth from ~85% down to 50% thinking if I had plenty of fuel then I might benefit from more water in the mix (trims did go up a bit, but still lower than ever) Even with no check engine lights and fairly strong WOT performance I think this code (or really the sensor being jacked up) is messing with things.

[themyst]

Originally Posted by Indo Rider

Wow, me too! I even cut my meth from ~85% down to 50% thinking if I had plenty of fuel then I might benefit from more water in the mix (trims did go up a bit, but still lower than ever) Even with no check engine lights and fairly strong WOT performance I think this code (or really the sensor being jacked up) is messing with things.

yep same thing. wont notice a problem if you dont log or know what to look for.

[Jklad]

Has anyone had to replace the Fuel Pipe that the sensor connects to? Or should i ignore the pipe and just do the sensor to keep it simple?

My tech said that for older cars, the fuel inlet pipe that the sensor bolts into needs to also be replaced - the original pipe was too close to the engine, and the vibrations cause the sensor to fail prematurely. The new pipe should have a spacer of some sort that prevents this from happening.

The kit is $120 on RealOEM and includes parts # 13537614317 Sensor and 13537622751 Inlet Pipe (03/07 build)

[Jklad]

Originally Posted by Jklad

Has anyone had to replace the Fuel Pipe that the sensor connects to? Or should i ignore the pipe and just do the sensor to keep it simple?

My tech said that for older cars, the fuel inlet pipe that the sensor bolts into needs to also be replaced - the original pipe was too close to the engine, and the vibrations cause the sensor to fail prematurely. The new pipe should have a spacer of some sort that prevents this from happening.

The kit is $120 on RealOEM and includes parts # 13537614317 Sensor and 13537622751 Inlet Pipe (03/07 build)

So to answer my own question, my parts guy confirmed with one of his techs that the new procedure calls for replacing both the low pressure sensor and the fuel inlet pipe it goes into. Going this route requires and new aluminum bolt to replace the one time use inlet pipe bolt, and theres a different part number and fitment for the new sensor that plugs into the new inlet pipe.

They didn't stock the inlet pipe, and The shop said Its fine to just replace with a replacement sensor (old part#), but that it will likely fail again at some point, hence BMWs updated inlet pipe.

I decided to save some cash and time by buying only the old style sensor so I dont have to go through the trouble of replacing the inlet pipe.

[new2the3]

Will the dealer fix this under the 8/80 emissions warranty? I have the shadow code too but no apparent symptoms other than bad mpg

[UMich_335i]

My Cobb AP is logging lpfp psi at 145 psi constant. I also have the p29f3 code, is this the faulty sensor value?

[UMich_335i]

Also saw theres two options on RockAuto for $48 and $68, Airtex/Wells and Standard Motor Products brand respectively.

[j1gilles]

Originally Posted by UMich_335i

Also saw theres two options on RockAuto for $48 and $68, Airtex/Wells and Standard Motor Products brand respectively.

Sounds like the sensor to me... Go with the one from Tischer BMW, I think it is around $70 and is OEM.

[UMich_335i]

Tackled this sensor replacement over the past two days and wanted to add my comments/suggestions:
1. I am a novice, this took me about 4 hours (included massive struggles with the junction box and having to get a few tools I didn't have), I could get it done way faster if I had to do it again though.
2. I tried to make the tool shown in the DIYs but it ended up being too big and didn't work. Instead, I used a small metal pick to get under each of the 4 latches to clear the debris that has built up in the 5 years of the car's existence. This worked very well, box just slid off after.
3. The space is much smaller than I was expecting once I got the junction box off. For a guy with bigger hands it was a struggle, but just take your time and be patient.

Hope this helps some people attempting to do this in the future. LPFP pressure is back down around 72psi instead of pegged at 145.

[greg328]

Originally Posted by new2the3

Will the dealer fix this under the 8/80 emissions warranty? I have the shadow code too but no apparent symptoms other than bad mpg

This...

??

Greg

2008 335i Coupe
same code--29F3

[Welterweight]

Having this code pop up intermittently on my Cobb ap. Comes and goes with no signs or symptoms.

Should I order part? Matter of time?