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Problems With Fuel Gauge

johnr
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johnr Enthusiast

johnr

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Hi,

Has anyone had problems with their fuel gauge/fuel tank? My fuel gauge was working fine but recently it varies wildly from 3/4 full to full. Also I cannot fill the tank more than about 3/4 full and there seems to be an air lock or something - even after shaking the car during filling, I can't fill the tank. Any clues?

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johnr Enthusiast

johnr

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Is it a mere faulty in-tank gauge signal reading or do you actually can only put less litres of petrol in your tank when refilling?

Both; I can't completely fill the tank and the fuel gauge moves from full to 3/4 full

NISMO Grand Master

NISMO

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Both; I can't completely fill the tank and the fuel gauge moves from full to 3/4 full

hey John,

Go as close to empty as possible and then fill up and see how many litres go in.

It does sound like a faulty guage, and i know that the fuel gauges/sensors in our cars and 350z are nothing short of crap.

I've filled up to the point where it just about overflows out, and the guage shows half a quarter to go. I can also be at half tank and within 5k's it shows close to a quarter left :P

johnr Enthusiast

johnr

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LOL - i thought nissan should have fixed them (fuel gauge sensor) 10 years after the R33....

I think my gauge is stuffed as well I have some sort of air lock in the tank as the maximum I can put in is about 55 litres. Any clues on how to fix it???

  • 1 year later...
johnr Enthusiast

johnr

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I think my gauge is stuffed as well I have some sort of air lock in the tank as the maximum I can put in is about 55 litres. Any clues on how to fix it???

I fixed the fuel gauge problem and it was easy. All you have to do is clean the sliding connections on the 2 fuel floats.

Take out the rear seat, expose the both openings to the 2 floats, withdraw the left float but just lift the right to expose the contacts and get a cotton bud to clean the sliding connections on both the floats. They don't seem dirty when you first see them but when you run the cotton bud over them you get a black oxide on the bud which is affecting the fuel gauge reading. Only takes about half hour.

n15m0 Grand Master

n15m0

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I fixed the fuel gauge problem and it was easy. All you have to do is clean the sliding connections on the 2 fuel floats.

Take out the rear seat, expose the both openings to the 2 floats, withdraw the left float but just lift the right to expose the contacts and get a cotton bud to clean the sliding connections on both the floats. They don't seem dirty when you first see them but when you run the cotton bud over them you get a black oxide on the bud which is affecting the fuel gauge reading. Only takes about half hour.

Pics would be good.

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johnr Enthusiast

johnr

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Hi Mate,

I've also had this problem where I can only fill up to about 3/4 full. I can only ever fill up around 40L max.

Also petrol gauge is all over the shop. Decides to move whenever she pleases.

That is exactly what mine was doing and now it seems to be stable and accurate. When I cleaned the connections today I noticed that the tank was half full of fuel when the gauge indicated that it was nearly empty. I have only taken it for a short drive and it seems accurate now and doesn't go all over the place; I will have to wait and see if it is permanent but the US forums seem to think that this is a good fix.

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