Engine run out of fuel?

[adriang]

For the past few months I've been having a problem with my 2009 bmw x5d.

It seems like the engine runs out of fuel and the car stops when the cluster indicates a 1/4 tank now sometimes before the low fuel light goes on. Earlier it would run out at about 1/8th of a tank left. Cluster indicates the half engine and car goes in limp mode just before turning off

I suspect its fuel related but not sure if its the pump or not. The dealership had performed a scan but didnt find anything. Anyways I thought it would be the floating leveler so it was replaced along with the fuel filter but the problem still continued.

In any case I had a look inside the fuel tank today to see if its dirty inside but it seemed clean and also looked to see if the floating leveler is being obstructed in any way but its not.

My last best uneducated guesses are that the fuel pump is not performing well when it is no longer fully submerged in the fuel or the fuel pump relay is playing tricks with my fuel pump.

What do you guys think?

[Chihuahua]

DEF reservoir full when this happens?

[adriang]

Yes its full,
I've been reading about a bad sender unit over at m3 forums... hmm maybe thats it?

[Chihuahua]

I think that tank has two fuel pumps, one for each side of the 'saddle' in the tank. Maybe one of the pumps is out?

[adriang]

Is this what you're talking about?
http://www.realoem.com/bmw/showparts...59&hg=16&fg=15

[Marilyn Horne]

I've heard conflicting opinions on this, so just wanted to see what people think. It's obviously not a good thing to run out of fuel in the middle of a journey, and it's not something that I've done, or planning on doing.

[Chihuahua]

Originally Posted by adriang

Is this what you're talking about?
http://www.realoem.com/bmw/showparts...59&hg=16&fg=15

yes. I've seen this type of setup on other cars as well.

[adriang]

Fuel pump and sensor seems to have been my issue

[Chihuahua]

Glad you got it resolved.

[adriang]

we'll see once and for all after it's out of the shop! I'll let you guys know as I'm sure others will find this information useful too

Edit:

Both sensors were giving out of spec resistance readings so both had to be changed. One of the sensors were connected to the fuel pump so it was changed also. Basically all this was changed http://www.realoem.com/bmw/showparts...59&hg=16&fg=15
We shall see next time I go low on fuel if it leaves me stranded or not

Edit2: back in the shop with same problem...

[note46]

get this resolved yet? how old is the fuel filter?

[adriang]

Originally Posted by note46

get this resolved yet? how old is the fuel filter?

Not yet still at dealership. Fuel filter was the first thing that was replaced about 6 months ago

[adriang]

They haven't found the issue The dealership was in contact with BMW Canada and had done everything BMW Canada technicians said for the mechanics to do.

Took the car in but they were not able to find out what is wrong. However, this time around after the shop visit the car got to about 15 km of fuel remaining in the tank, before I decided it was time to fill up because I didn't want the engine to run out again.

In any case, if it happens again the dealership told me to bring it in to the shop and that they opened up a puma(?) case to further examine the problem with more knowledgeable mechanics (I assume)