How Low Can The Fuel Go ?

[tckhor]

Dear forummers,I own a 523i E39 year 2000 local CKD model (M52B25TU). Lately I noticed that the car does not tolerate too low a fuel level in the tank. In the past, I could go until the low level warning light comes on but lately with a quarter tank left. the engine appears to suffer from fuel starvation, at one point even causing the engine to stall. I wonder if fellow forummers have encountered a similar situation with their cars and if so, what is the likely cause and how can this problem be rectified. Thank you for sharing.

 

[IsaacVky]

Always fill up your tank when there's a quarter left or you're damaging your fuel pump.

 

[fabianyee]

Probably the fuel pump is already on the way going down south if that's he's been running the tank dry most of the time.

 

[hussein38]

My trnmission hard when push to ( p ) why ?

probably the fuel pump is already on the way going down south if that's he's been running the tank dry most of the time.

when i put my tranmission at p very hard to push anybody got idea why this problem happen?

 

[jarance]

when i put my tranmission at p very hard to push anybody got idea why this problem happen?

dude, please start your own thread for your problem.. :wink:

 

[jarance]

If your fuel pump cannot operate on low level, chances are that

1. your pump is on the verse of breaking down
2. or your fuel filter is dirty and need to be replaced. The reason being that if your filter is choked, the pump need
more power to deliver fuel to the fuel rail. When the level is low, the suction head is low and hence the discharge
pressure would be reduced and hence will result in low fuel pressure.

Change the filter first and then the fuel pump if the problem presist.

 

[m43ldotcom]

i guess this problem affect most of the e39 (sooner or later) because my uncle e39 523 also behave like that last time. my uncle manage to drive back home and engine stall in front of the house gate. try to start again, no use because it run for couple of seconds before stall back. then need to push it to the side ... really heavy i tell you

he replace the fuel filter, and some time later replace the fuel pump but the problem still exist (but not stalling .. just jerking a little bit sometime).

so ... what to do ... no time (and not enough money) to continue rectify the problems ... so he change car (to e46 .... next year maybe e60 ... huhu .. really bad economy this year)

in the end i also dont know what is the real problem .... hope the buyer of that car can cure it.

 

[turbology]

2. or your fuel filter is dirty and need to be replaced.
Change the filter first and then the fuel pump if the problem presist.

I 2nd the decision.
Try some fuel system cleaner.
Cheers

 

[fabianyee]

There's a reason why u should never run the tank dry all the time... the fuel pump in most BMW's since the earlier 90s are internal units, so it is submerged in the fuel for both cooling and noise & vibration insulation... If you run with low fuel all the time, the pump will not get the cooling effect it should be getting, hence the premature failure...

 

[davidtch]

Since ur E39 is Y2k, chances of fuel pump is very high. I would suggest to change fuel filter (if u haven't change it yet) & fuel pump. I kena fuel pump failure & stall on d road. In d end, hav to tow to workshop.

 

[tckhor]

A big thank you to all the forummers who have all given very useful information indeed. I read somewhere the tank has two compartments - the left and right compartments. The main fuel pump is located in one compartment and there is a transfer pump between the two. Is this true and if so, could this be a source of problems as well ? Thanks for your valued contributions.

 

[initialM]

The fuel pump located on the right side while the float on the left.
Check out the pic on my link

http://www.bmwclubmalaysia.com/forums/showthread.php?t=8855&page=62