*Confirmed* HPFP failure on my 2011 N55 135i

[lavmugen]

Please refer to my previous post from my trackday 1 week ago:
http://www.1addicts.com/forums/showthread.php?t=444576


Long story short:
1. went to trackday
2. drove like crazy
3. run out of fuel last session
4. reduced engine power + check engine light
5. car felt sluggish, poor throttle response
6. took it in for service, initial code pulled was "low fuel rail pressure"
7. got a call today from BMW that the fuel pump had failed and was replaced

disclaimer:
1. car has 15000 km, 9400 miles currently (stock)
2. march 2010 build date
3. had 2 longish cranks in the past (both after stalling, NOT cold starts)
4. i was running HARD when i ran out of fuel on the track that may have lead to the failure of the HPFP
5. i do not believe the fuel pump was defective, and instead i believe i have contributed to the damage

Hopefully i'll get the car back tomorrow and give everyone an update on the diagnoses, fuel pump part no, etc.

[escobar929]

didnt read the other thread but not surprised it failed after running out of gas. some say one of the key issues of the pump lasting is not to let it go down under 1/4 tank

[MarkR171]

Sounds like you might be right, low fuel + pushing hard = overworking the fuel pump = failure.

[lavmugen]

that's what i was thinking....

it didnt fail on me, and instead i broke it.

[bryce]

maybe it's the problem solving side of my personality, but i think we can learn something from this. if the low pressure pump is having cavitation issues or issues delivering enough fuel, maybe that's the culprit of the hpfp plague.

if you run out of fuel and your hpfp fails, what does that say about the hpfp in general? it needs robust amounts of fuel to keep the engine running well, and if a fuel delivery problem from either the low pressure pump or an empty tank of gas, it goes.

see what i'm saying?

[RPM90]

I consistently run my tank below 1/4 tank. I like fresh fuel.

I've got 12.5K miles, no HPFP problems yet.
I have had a code for "low fuel rail pressure". They cleared it. Installed the updated software, I now have poor high rpm throttle response, but other than that all is well, so far.

I'm not buying that running out of fuel is abuse, nor the cause of the failure.
If running out of fuel is the cause, then it's a fault with the pump design.
It's not unusual for people to run out of fuel. The system needs to be designed to anticipate that potential.
It doesn't take much to write code to shut down the system if the low pressure pump sees no fuel, in advance of the HPFP getting starved of fuel.

The issue with running out of gas, since the advent of fuel injectors, has been a potential failure of the fuel injectors running dry with a "potential" for failure due to getting fouled. I've never heard of a fuel pump going dead due to running out of gas.
I have heard of a pump failing if you keep cranking to start the engine with no fuel.

But then, it's a new thing with DI and high pressure systems, so teething problems can happen.
Still, I wouldn't blame the owner. The system should be smarter than that. This ain't 1985.

[lavmugen]

UPDATE:

got my car back today from the dealership. They swapped the HPFP with the exact same (i believe still the latest version) part. 13-51-7-613-933.

also did a Program Control Unit (HFM) update?

and a repair to the sound insulation?

all covered under warranty. car is back to normal now. pulls hard =)

[atr_hugo]

Originally Posted by bryce

maybe it's the problem solving side of my personality, but i think we can learn something from this. if the low pressure pump is having cavitation issues or issues delivering enough fuel, maybe that's the culprit of the hpfp plague.

if you run out of fuel and your hpfp fails, what does that say about the hpfp in general? it needs robust amounts of fuel to keep the engine running well, and if a fuel delivery problem from either the low pressure pump or an empty tank of gas, it goes.

see what i'm saying?

I've had a couple of 'long' starts after the car has been sitting a day or two and I've tried a new strategy when starting it (it's a manual tranny car). I keep my foot off the clutch and hit the start button, energizing the car and probably the low pressure fuel pump. After a few seconds I stick my foot on the clutch and start the car. It seems to work. Anyone else try this?

[Thaddy]

The title of this thread should be changed to "I broke my HPFP in my 2011 135i." Glad your car is working, but the title is very misleading.

Originally Posted by atr_hugo

I've had a couple of 'long' starts after the car has been sitting a day or two and I've tried a new strategy when starting it (it's a manual tranny car). I keep my foot off the clutch and hit the start button, energizing the car and probably the low pressure fuel pump. After a few seconds I stick my foot on the clutch and start the car. It seems to work. Anyone else try this?

This is most likely initiating the fuel pump and priming the fuel system before you start the car. The fuel pump in my WRX is very loud and I'll listen for it to engage for a few seconds before starting the car. It's very helpful in the winter months and when the car has been sitting for a while.

[merlinbk]

Originally Posted by lavmugen

UPDATE:



and a repair to the sound insulation?

.. yeah they remove some of your side panel insulation.