Fuel Gauge Issue

[ChipUK]

The last 2 times that my fuel gauge has got towards a 1/4 tank left as soon as I'm in traffic and ticking over the gauge drops to zero and the fill up warning light comes on. As soon as I start driving along the gauge recovers to normal. Any ideas? Electrical?

 

Thnx in advance...Chip

[RobLarby]

Mines done this twice in the last two years and I've never thought anything of it, not sure if it's an issue

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[ChipUK]

Hmmmmm never done it before though. Nice to know I'm not alone :|

[cheshire_cat]

sounds like voltage drop   start with a battery load test,    do you have "miles left in tank" ?

[ChipUK]

sounds like voltage drop   start with a battery load test,    do you have "miles left in tank" ?

 

Hi Cheshire cat

 

Sorry for the delay in replying What happens is - the fuel gauge works fine until just before it gets to the red line. Still works fine so long as not stuck in traffic and on tickover. If so, then the fuel gauge drops to zero, red warning light comes on and 'miles left' goes to zero.

[Peterj222]

Hi Cheshire cat

 

Sorry for the delay in replying What happens is - the fuel gauge works fine until just before it gets to the red line. Still works fine so long as not stuck in traffic and on tickover. If so, then the fuel gauge drops to zero, red warning light comes on and 'miles left' goes to zero.

Had exactly the same on the missus 07 Vrs, plugged into vagcom and tested instrument cluster and noticed that the fuel remaining and sender resistance went doolally when you gave the car a slight rock from side to side. This only happened when it was near quarter of a tank. Took the fuel gauge sender out of the tank (Its part of the electric lift pump accesed from under the back seat) and found the whole assembly was coated in a sort of black soot I dont know if this is normal?? I cleaned the tracks very carefully with a peice of soft cloth soaked in petrol, put it back together and its never done it again. There should be a slight change in the reading if you gently rock the car but mine was jumping up and down erratically...and now its not.

I would add that if you want to try this run the car as low on Diesel as you can beforehand otherwise it could be a very messy job!!

[ChipUK]

Had exactly the same on the missus 07 Vrs, plugged into vagcom and tested instrument cluster and noticed that the fuel remaining and sender resistance went doolally when you gave the car a slight rock from side to side. This only happened when it was near quarter of a tank. Took the fuel gauge sender out of the tank (Its part of the electric lift pump accesed from under the back seat) and found the whole assembly was coated in a sort of black soot I dont know if this is normal?? I cleaned the tracks very carefully with a peice of soft cloth soaked in petrol, put it back together and its never done it again. There should be a slight change in the reading if you gently rock the car but mine was jumping up and down erratically...and now its not.

I would add that if you want to try this run the car as low on Diesel as you can beforehand otherwise it could be a very messy job!!

Ok Thnx for the info! V useful. I'll clean the sender and see how I get on....

[cheshire_cat]

Ok Thnx for the info! V useful. I'll clean the sender and see how I get on....

I wouldn't get too enthusiastic about doing a good job by either removing the two small wires or the "resistance" board as it's glass/ceramic and easily cracks  just a light clean as above-----------------  don't ask how I know

[Peterj222]

I wouldn't get too enthusiastic about doing a good job by either removing the two small wires or the "resistance" board as it's glass/ceramic and easily cracks  just a light clean as above-----------------  don't ask how I know

Yeah they look pretty fragile!! Out of interest Cheshire I take it you had yours apart? Was yours sort of sooty / dusty?? I couldnt work out how mine had got like it soon as it sits in the tank submerged in Diesel most of the time??

[cheshire_cat]

no mine was clean,  but as the  one before was a wire wound one and  it was covered in a sort of laquer hence the thoro' clean this time,-----  I can only guess the black goo? is bacterial contamination

Edited 25 May, 2016 by cheshire cat