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Jon K
06-06-2006, 08:46 PM
So just recently the car, a 1995 530i, has trouble displaying correct fuel level. I am thinking it has something to do with a capacitor but I am not sure that this affects the gauge or not so I figured I'd ask. Even if the car has 100% full fuel tank, the gauge is off by more than 3/4 of a tank, indicating 1/4 tank or less. I really hope this is not the fuel tank level sender, as I hate reaching in the depths of petrol, but I guess I will find out from the crowd. One thing worth mentioning is that when the tank is full, the car turned on, the gauge goes from 0 (like normal) to the 1/4 or so but reaaaaal slow.

Has this happened to anyone before, and if so, what was the fix?

On another note, i notice my fuel gauge is relatively inaccurate beloew 1/2 or 3/8 full... similar issue or different?

Blitzkrieg Bob
06-06-2006, 08:59 PM
Does the range reflect the level of the tank?

If the range reading goes up like mine to 400++ after a fill up, then it is probably the sender.

May be stuck, sometimes the outer sleeve comes loose and blocks the float travel.

Jon K
06-06-2006, 09:02 PM
I will check it tomorrow. I have to ask her how much fuel is actually in it.

shogun
06-06-2006, 09:11 PM
http://bmwe32.masscom.net/johan/fuel_sender/fuel_sender.html

genphreak
06-06-2006, 09:28 PM
Interestingly mine shows 1/4 if I leave the car running when filling it up from empty (isn't that dangerous- but when I'm talking on 2 cell phones at once AND working the pump there's often just too much happeneing to cover everything...) :)

The cap must need to have the ignition turned off in order for it to reset, otherwise the gauge will creep up ever so slowly as you drive along with your newly filled tank afterwards...

I know it doesn't help- but as an observation it might have some value one day.

I find that the gauge is pretty accurate apart from that.

:) Nick

Alexlind123
06-06-2006, 09:42 PM
Interestingly mine shows 1/4 if I leave the car running when filling it up from empty (isn't that dangerous- but when I'm talking on 2 cell phones at once AND working the pump there's often just too much happeneing to cover everything...) :)

The cap must need to have the ignition turned off in order for it to reset, otherwise the gauge will creep up ever so slowly as you drive along with your newly filled tank afterwards...

I know it doesn't help- but as an observation it might have some value one day.

I find that the gauge is pretty accurate apart from that.

:) Nick

Talking on cell phones while pumping gas can cause explosions. Talking on two doubles your chances!!

rob101
06-06-2006, 09:54 PM
Talking on cell phones while pumping gas can cause explosions. Talking on two doubles your chances!!
LOL
no it doesn't thats just something mothers tell their children to scare them

Not touching the metal body of the car when you get out and then using the pump causes explosions.

genphreak
06-06-2006, 11:51 PM
LOL
no it doesn't thats just something mothers tell their children to scare them

Not touching the metal body of the car when you get out and then using the pump causes explosions.Heh true bud. Better tell my gf never to do that, she zaps everthing- not only me ;)

You know Rob, in the US the pump has a seal to go round the filler nozzle- for the phone issue as well as an even better reason:

The Benzene fumes are more carcinogenic than lead. After combustion things improve (ie its a cleaner additive in general terms than lead... but the fumes off the liquid fuel (ie at the petrol station) are freakin bad for you. This is why the lawyers scared the gas comanies into sealing the pump nozzles off. Also it is still lethal post-combustion due to the increasing use of vehicles (in ever increasing densities); post-combustion benzene levels are becoming a serious problem in heavily trafficked cities (especially for people in the cars and even more so the pedestrians). Of course people think its clean cos they can't see the pollution... and/or think there is no lead so its got to be OK nowadays... bwahahahaha! how wrong they are ;) we are all going to die, and some of us more horribly than others... :) Nick

THe other take home is never get petrol on your hands- I imagine Benzene is easily absorbed directly through the skin as it is through the lungs and eyes... :p

saj3n
06-07-2006, 03:25 PM
Interestingly mine shows 1/4 if I leave the car running when filling it up from empty (isn't that dangerous- but when I'm talking on 2 cell phones at once AND working the pump there's often just too much happeneing to cover everything...) :)

The cap must need to have the ignition turned off in order for it to reset, otherwise the gauge will creep up ever so slowly as you drive along with your newly filled tank afterwards...

I know it doesn't help- but as an observation it might have some value one day.

I find that the gauge is pretty accurate apart from that.

:) Nick


My car actually gets more mileage when I fill up the tank with engine running.... (done once by accident, tempted to do again... :-P)

rob101
06-07-2006, 03:44 PM
Heh true bud. Better tell my gf never to do that, she zaps everthing- not only me ;)

You know Rob, in the US the pump has a seal to go round the filler nozzle- for the phone issue as well as an even better reason:

The Benzene fumes are more carcinogenic than lead. After combustion things improve (ie its a cleaner additive in general terms than lead... but the fumes off the liquid fuel (ie at the petrol station) are freakin bad for you. This is why the lawyers scared the gas comanies into sealing the pump nozzles off. Also it is still lethal post-combustion due to the increasing use of vehicles (in ever increasing densities); post-combustion benzene levels are becoming a serious problem in heavily trafficked cities (especially for people in the cars and even more so the pedestrians). Of course people think its clean cos they can't see the pollution... and/or think there is no lead so its got to be OK nowadays... bwahahahaha! how wrong they are ;) we are all going to die, and some of us more horribly than others... :) Nick

THe other take home is never get petrol on your hands- I imagine Benzene is easily absorbed directly through the skin as it is through the lungs and eyes... :p
its actually funny that benzene was replaced by lead additives because benzene is very harmful,
how far we have come in 80 years.
Yeah i saw a mythbusters where they tested the phone thing
BUSTED, there is no way that the phone emits enough radition to cause an explosion. or for that matter create a spark.

anyway i am going to make some "clean energy" from hydrogen which we got from electrolysing water using power from a coal fired power plant. Such progress we've made, especially in the realm of the bliss/ignorance duality!

romus
06-07-2006, 04:00 PM
I've had similar problem ever since I had the car. Mine on the other hand stays on zero even when full, then goes beyond "full", the arm sits on 90 degree angle to the right! Then shows half when it's almost full etc. I've never run out of fuel, 'coz I don't rely on the gauge. But I'd be interested to know what the problem is.

romus
06-07-2006, 04:04 PM
hey Bob I'll add my detail to this. After a full fill up mine used to go 580+ on OBC but gauge still stays zero or wherever. Just recently it developed a habit of sticking to whatever number there was before fill up, only to change hours later.

Blitzkrieg Bob
06-07-2006, 04:07 PM
But if you guage is dead and the OBC is doing a decent job of calculating your range then it's probably the guage, or the wiring to the guage, since the sender drives both the guage and OBC.

romus
06-07-2006, 05:41 PM
OBC used to take no time at all recalculating. By the start up from the gas station I'd press range and it would already be recalculated. Recently tho it started holding the "old" range for hours after fill up.

Thanks

Alexlind123
06-07-2006, 10:25 PM
Heh true bud. Better tell my gf never to do that, she zaps everthing- not only me ;)

You know Rob, in the US the pump has a seal to go round the filler nozzle- for the phone issue as well as an even better reason:

The Benzene fumes are more carcinogenic than lead. After combustion things improve (ie its a cleaner additive in general terms than lead... but the fumes off the liquid fuel (ie at the petrol station) are freakin bad for you. This is why the lawyers scared the gas comanies into sealing the pump nozzles off. Also it is still lethal post-combustion due to the increasing use of vehicles (in ever increasing densities); post-combustion benzene levels are becoming a serious problem in heavily trafficked cities (especially for people in the cars and even more so the pedestrians). Of course people think its clean cos they can't see the pollution... and/or think there is no lead so its got to be OK nowadays... bwahahahaha! how wrong they are ;) we are all going to die, and some of us more horribly than others... :) Nick

THe other take home is never get petrol on your hands- I imagine Benzene is easily absorbed directly through the skin as it is through the lungs and eyes... :p

Thanks alot!! That will give me something to think about when i swap my fuel sender on friday...

mikell
06-08-2006, 02:32 PM
So, is there a conclusion or a consensus on this? If the OBC agrees with the gauge, then it's the sender, but if not, then what? Capacitors? Really interested from the trouble shooting point of view, since my gauge has been refusing to go above 7/8ths full on a fill up for about 2 weeks now. Thanks.

Jon K
06-08-2006, 02:48 PM
Waiting for her tank to run down. I filled it up and it says ~400 miles or whatever, shes been driving but it happened last time around 1/4 tank.

genphreak
06-08-2006, 07:39 PM
Thanks alot!! That will give me something to think about when i swap my fuel sender on friday...Yea its not a fun job that... I don't envy you. With the hands issue I keep a rag handy and don't start the job with freshly cleaned hands. Other than that I just avoid touching the petrol as much as possible. Good luck- the main hassle is avoiding the fumes... again, as with everything automotive it is far less than a perfect science. :) nick

Jon K
06-08-2006, 07:42 PM
At least its accessible I think thru the trunk - the S-type jags we did were inside - had to remove rear seat. The fumes got so trapped in there it was so bad.

Alexlind123
06-08-2006, 07:50 PM
At least its accessible I think thru the trunk - the S-type jags we did were inside - had to remove rear seat. The fumes got so trapped in there it was so bad.

I actually dont remember if i have to unlatch the fuel pump or if the sender just pulls right out.