Fuel gauge stopped working???

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MurphyE30
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Thu Feb 17, 2011 6:48 am

driving in to work this morning all was normal and then my fuel gauge pin started bouncing from empty to full repeatidly and know wont stop.

anyone had this problem or know what this could be?

any help will be great :D

cheers
clipper
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Thu Feb 17, 2011 7:19 am

Brass nut on the back of the guage dropped off ?
These are sensations as hard to forget as they are to ignore.....
Grrrmachine
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Thu Feb 17, 2011 9:27 am

The fuel senders use a plastic float bridging two sides of a resistive wire; as the float goes up and down, the effective length of the wire is reduced, telling the guage how much fuel there is.

Unfortunately, this wire is hair-thin, and when it breaks it curls up against the aluminium lining of the fuel sender, reading either completely full or completely empty. There's two senders as well; one on its own on the left side of the tank, and another on the right side, built into the fuel pump. Both are accessible under the rear bench, under individual access hatches. You can't repair them unfortunately, but there's plenty of replacements around.
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cluke
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Thu Feb 17, 2011 1:02 pm

My gauge has started reading half of what is actually in the tank although it is still going up and down as the tank is filled and fuel is used.
I am sure it is the sender and have obtained some resistance measurements from google which should confirm the sender. Full should be around 5 ohms, empty should be around 80 ohms. May not be relevant in your case as the sender resistance sounds like it's breaking down.
Regarding the number of senders, I believe earlier cars (pre 1986) only had one sender as the tank is a single compartment.
craigieeb
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Thu Feb 17, 2011 4:48 pm

Did it do something like this Murphy...


M50 Turbo!!! :o I shall say no more :D
MurphyE30
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Thu Feb 17, 2011 8:07 pm

craigieeb wrote:Did it do something like this Murphy...


yeah thats it mate
craigieeb
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Thu Feb 17, 2011 8:15 pm

That's what happened to mine mate, (obviously, my vid haha)

I changed the sender in the petrol tank (left side)
and it was sorted
M50 Turbo!!! :o I shall say no more :D
MurphyE30
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Thu Feb 17, 2011 8:18 pm

so i will just need a sender. cheers mate

i might just chuck it into garage saturday while im at work
craigieeb
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Thu Feb 17, 2011 8:21 pm

Ring,
GSF or ECP and just buy one and fit it you lazy fecker

:P
M50 Turbo!!! :o I shall say no more :D
MurphyE30
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Thu Feb 17, 2011 8:23 pm

craigieeb wrote:Ring,
GSF or ECP and just buy one and fit it you lazy fecker

:P
is that you offering to fit it if i buy one winkeye
craigieeb
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Thu Feb 17, 2011 8:28 pm

No

But i'll lend you a pair of gloves so you dont even get your hands dirty


:lol: :lol:
M50 Turbo!!! :o I shall say no more :D
MurphyE30
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Thu Feb 17, 2011 8:33 pm

HAHA got plenty of gloves here :lol:

is it a simple swap? how would i go about it?
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colinurquhart
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Thu Feb 17, 2011 8:33 pm

It was my left ones (passenger) that went too. I'm no mechanic or expert but its an easy job to do yourself. Goodluck
craigieeb
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Thu Feb 17, 2011 8:34 pm

Piss easy,

i'll talk you through it tomorrow
M50 Turbo!!! :o I shall say no more :D
MurphyE30
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Thu Feb 17, 2011 8:35 pm

Ok mate :cool:

should be round about half 3
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