[DiFFv1]

Hello, i know that you can find this issue on the forums and i have been doing my digging but came up with nothing. My good friend is having some fueling issues. First let me start with what we have found and tried to solve so far...

Monitored the Fuel Rail Pressure - Has Dropped to about 668.90 But has maintained 750-800+ on most startups/At idle. Delayed 3-5 second cranks whether cold weather or not. tried priming pumps before start, Most times 2nd startup will turn the engine over.

Under any load or WOT 1,200-2,200+ On the rail pressure, Not bogging during acceleration but it does at a stop or in park sometimes.

LPFP is upgraded - Check and rechecked again, Thinking of gauging/Testing the pressure there.

Code: 2BDE - Fuel high pressure on enabling of injection: pressure to low.

Car: 03/2011 N55

Parts Considering To Purchase:

13537620946 - Bosch Fuel Pressure Sensor
13517616446 - HPFP
11787596924 / 11787589475 - Pre Cat o2 Sensor


Need any additional info let me know, Trying my best to fix and keep him on the road. Any suggestions or good feedback would be greatly appreciated!

[HeyTeeee]

I feel your pain! Hopefully the more seasoned owners have a solid diagnostic plan. I can tell you with mine I had shadow codes 2BDE & 2BF0 + the long crank issue. I replaced the HPFP & fuel rail sensor now both codes are gone as well as the long crank. Probably didn’t need to replace the sensor...but I was already there and with no real knowledge of previous maint done on the car I figured why not I’m already there. I’ve still got a random rail spike issue when at a stop but those codes havent returned yet.

[Kevin39]

I'm going to be doing this soon as well. I've had the same 2BDE and 2BF0 shadow codes for a little while but it's not been a problem yet so I've been putting it off. Now I've got some valvetronic issues going on as well so it's time for some maintenance work.

[DiFFv1]

Originally Posted by HeyTeeee

I feel your pain! Hopefully the more seasoned owners have a solid diagnostic plan. I can tell you with mine I had shadow codes 2BDE & 2BF0 + the long crank issue. I replaced the HPFP & fuel rail sensor now both codes are gone as well as the long crank. Probably didn’t need to replace the sensor...but I was already there and with no real knowledge of previous maint done on the car I figured why not I’m already there. I’ve still got a random rail spike issue when at a stop but those codes havent returned yet.

Yes brother! chasing down whatever this issue is. but i just test the battery on startup and it hit 10.17V so i'm replacing that as we speak. May i ask where you got your HPFP from/Part #

[DiFFv1]

Originally Posted by Kevin39

I'm going to be doing this soon as well. I've had the same 2BDE and 2BF0 shadow codes for a little while but it's not been a problem yet so I've been putting it off. Now I've got some valvetronic issues going on as well so it's time for some maintenance work.

Yes sir i suggest getting to the issues now before it gets worst. Glad my post could push you! ha

[HeyTeeee]

I have purchased nearly everything from FCPEuro that lifetime warranty is too good to pass up. Part no for my car (build date 9/2010) 13517616446 and the gasket: 13517571363. Some posts say you can replace it without removing the intake some say it’s a must. I opted to remove it and replaced the gaskets 11617547242 and the throttle body gasket 13547582931. I followed this diy for the n54 it’s nearly the same for our n55 https://www.fuel-it.com/how-to-replace-your-hpfp/

[DiFFv1]

Originally Posted by HeyTeeee

I have purchased nearly everything from FCPEuro that lifetime warranty is too good to pass up. Part no for my car (build date 9/2010) 13517616446 and the gasket: 13517571363. Some posts say you can replace it without removing the intake some say it's a must. I opted to remove it and replaced the gaskets 11617547242 and the throttle body gasket 13547582931. I followed this diy for the n54 it's nearly the same for our n55 https://www.fuel-it.com/how-to-replace-your-hpfp/

Bless you!

[SnapCoupe]

I believe I am currently going through the same issues. I started a thread on it here: https://www.e90post.com/forums/showthread.php?t=1567669

Read my initial and last post, as it may help with your situation as well.

[E92TiAg335i]

Interesting. Subscribed.

[DiFFv1]

Originally Posted by SnapCoupe

I believe I am currently going through the same issues. I started a thread on it here: https://www.e90post.com/forums/showthread.php?t=1567669

Read my initial and last post, as it may help with your situation as well.

Checking it out now. Thank you

[DiFFv1]

Bump** Update: So i replaced the battery with a brand new one

First Cold start at 50 degrees - No hesitation startup normal.
Threw a code 36FD - DME main relay, plausibility: prematurely dropped out After clearing and Reset adaptations code went away. (i'm sure the reasoning was the new battery install, Same brand battery)

After reading up on SnapCoupe Post i went ahead an purchased the Fuel Pressure Regulator Repair Kit from FCPeuro https://www.fcpeuro.com/products/bmw...ft-16117163295 being that the 2011 N55 guys dont have a LPFP sensor unless Tee'd into the line. ( I know the LPFP is good)

Flashing back to an E50 tune and will update you on any new codes or issues. I next day'd the part so if any codes arise again i will install re-run tune and update you all.

I honestly feel its better to start spending $100 than $600-1k We will see what happens. Yall have a good 4/20 and happy Easter

[HeyTeeee]

Look forward to an update!
I might be going the same route, I left MHD connected for about 30/45mins to watch the rail pressure and it went from 73.5 down to 31 down to 17psi. I read in one of the bmw university things that the residual pressure shouldn’t drop more than .5bar in 30 min time. Not sure if that was engine specific but right bow it’s my only lead.

[DiFFv1]

Originally Posted by HeyTeeee

Look forward to an update!
I might be going the same route, I left MHD connected for about 30/45mins to watch the rail pressure and it went from 73.5 down to 31 down to 17psi. I read in one of the bmw university things that the residual pressure shouldn’t drop more than .5bar in 30 min time. Not sure if that was engine specific but right bow it’s my only lead.

Yes sir! , Thats the tricky thing if you havent already replaced or upgraded your LPFP it could be the LPFP , Regulator i just ordered or the HPFP. But no matter what i will find out the solution

[Chris_Rav]

I have also been experiencing issues lately. Mainly a misfire at WOT and longer than usual cold starts. I tried plugs and coils and that did not fix it. So I believed it to be a fueling issue since I was also getting the 2BDE and 2BF0 shadow codes. I did this replacement yesterday. So far no shadow codes and the car starts on the first crank but the misfire still persists. I will update if the shadow codes come back but as of now they seem to be gone.

As for the hpfp install, I would say it is relatively straight forward and easy. I chose to remove the intake manifold as it made the job so much simpler. I would think it would be quite difficult and much more time consuming trying to work around the intake manifold.

Please update if the fuel regulator solved any of your issues.

[DiFFv1]

Originally Posted by Chris_Rav

I have also been experiencing issues lately. Mainly a misfire at WOT and longer than usual cold starts. I tried plugs and coils and that did not fix it. So I believed it to be a fueling issue since I was also getting the 2BDE and 2BF0 shadow codes. I did this replacement yesterday. So far no shadow codes and the car starts on the first crank but the misfire still persists. I will update if the shadow codes come back but as of now they seem to be gone.

As for the hpfp install, I would say it is relatively straight forward and easy. I chose to remove the intake manifold as it made the job so much simpler. I would think it would be quite difficult and much more time consuming trying to work around the intake manifold.

Please update if the fuel regulator solved any of your issues.

Update: Today i threw the 2BDE Code again. After work i plan to tackle this regulator job, I honestly believe its the regulator because after the car sits for a couple hours and without priming the system upon starting you (and i) get the hesitation on startup without the proper fuel in the lines causing a misfire on certain cylinders. i will check back in a day with an update. Doing all i can before forking out $550 to FCP Euro.

[HeyTeeee]

Originally Posted by DiFFv1

Update: Today i threw the 2BDE Code again. After work i plan to tackle this regulator job, I honestly believe its the regulator because after the car sits for a couple hours and without priming the system upon starting you (and i) get the hesitation on startup without the proper fuel in the lines causing a misfire on certain cylinders. i will check back in a day with an update. Doing all i can before forking out $550 to FCP Euro.

Right there with ya. I’ll be doing the regulator this weekend as well ANNNND replacing the valve cover if it arrives in time. I wanted to do the injectors those will have to wait

[SnapCoupe]

Originally Posted by DiFFv1

Update: Today i threw the 2BDE Code again. After work i plan to tackle this regulator job, I honestly believe its the regulator because after the car sits for a couple hours and without priming the system upon starting you (and i) get the hesitation on startup without the proper fuel in the lines causing a misfire on certain cylinders. i will check back in a day with an update. Doing all i can before forking out $550 to FCP Euro.

Looks like you'll end up getting the regulator done before I have the chance. Very excited to see the results. Sub'd to this thread. Feel free to post your results in my thread that I referred you to, as I probably won't be able to finish mine for another 2 weeks.

[DiFFv1]

Originally Posted by SnapCoupe

Looks like you'll end up getting the regulator done before I have the chance. Very excited to see the results. Sub'd to this thread. Feel free to post your results in my thread that I referred you to, as I probably won't be able to finish mine for another 2 weeks.

Just finished, No codes as of yet and she fired right on up! SN: Dont mind the Spiderman/Hulk Bandaid +3hp

[HeyTeeee]

Originally Posted by DiFFv1

Just finished, No codes as of yet and she fired right on up! SN: Dont mind the Spiderman/Hulk Bandaid +3hp

X) nice! How did it go? Also is your rail pressure dropping below ~700-750 during normal driving?

[DiFFv1]

Originally Posted by HeyTeeee

X) nice! How did it go? Also is your rail pressure dropping below ~700-750 during normal driving?

It went smoothly i recommend no more than about 3/4 tank of gas so you can have some room. Hardest part is feeding the lines, FYI also MAKE SURE you disconnect the connectors on the LPFP side and start the car (until car stalls out), This will release pressure from the lines and prevent you from getting a face full of fuel . The lowest ive seen the rail pressure before this install was 668.90 but it maintains 700-800 at idle.

[SnapCoupe]

Originally Posted by DiFFv1

It went smoothly i recommend no more than about 3/4 tank of gas so you can have some room. Hardest part is feeding the lines, FYI also MAKE SURE you disconnect the connectors on the LPFP side and start the car (until car stalls out), This will release pressure from the lines and prevent you from getting a face full of fuel . The lowest ive seen the rail pressure before this install was 668.90 but it maintains 700-800 at idle.

Nice! Stoked to see decent results so far. Really curious if it will stay consistent with firing right up on every cold start. Do you recall what your primed, pre-startup rail pressure was before replacing the regulator? Curious to see if it is higher now with the new regulator.

[DiFFv1]

Originally Posted by SnapCoupe

Nice! Stoked to see decent results so far. Really curious if it will stay consistent with firing right up on every cold start. Do you recall what your primed, pre-startup rail pressure was before replacing the regulator? Curious to see if it is higher now with the new regulator.

So far consistent Firing with NO hesitation at all.
Code: 2BDE is gone

I am still looking into shadow codes
Threw a 2BF0 [COLOR="DarkRed"]before[/COLOR] clearing codes after install ( Cleared did a couple pulls no code appearing as of yet )

i still believe there could be a potential HPFP replacement in the future, but this regulator definitely solves the misfiring and hesitation on standing starts and cold starts. Im the type of guy that cant stand seeing any codes so if any arise now i will be sure to take them on and try my best to solve them.