Just cant work out what the problem is!

[MrTackalakalaka]

Hello everyone

Ive been having problems with my fuel gauge on my 2000 S3........

I will fill my car right up to the brim and everytime, without fail the fuel light will come on and the gauge will read empty. The gauge and light will remain the same until i have done 100 miles approx (changes everytime) then it will normally go to a full tank, the light will also go off and the gauge stay there until ive got about a quarter of a tank left and it will drop to a quarter of a tank and wont go any lower, even if i run out of fuel.

I have fitted a new fuel tank unit.......that didnt work!

I then did a bit of research and found that a common fault is the cluster display......the LCD screen would have lines through it, the speedo and other gauges would also become faulty/incorrect. My LCD screen had lines through it but i wasnt sure about the other gauges.......anyhow I sent my cluster display off to BBA-Reman as I thought i might as well get the LCD screen replaced and see if there are any other faults.
Unfortunately they said there was nothing wrong with the fuel gauge on the unit but AT LEAST I have a nice shiney LCD screen that i can read now! haha

Now im back to square one!!

Anyone have any ideas with what could be wrong?

Thanks
Scott

[S3 Paul]

By fuel tank unit do you mean the whole thing that sits in the tank? ( got to under the rear seat of the car )?
I though the level sensor was in there? Is the breather to the tank open and clear? i only ask this as a woman i know has a golf 4motion that had issues with the gauge reading full and her only being able to half fill it because the tank basicaly needed to burp.

[MrTackalakalaka]

By fuel tank unit do you mean the whole thing that sits in the tank? ( got to under the rear seat of the car )?
I though the level sensor was in there? Is the breather to the tank open and clear? i only ask this as a woman i know has a golf 4motion that had issues with the gauge reading full and her only being able to half fill it because the tank basicaly needed to burp.

Hello

Yes it was under the rear passenger seat. Hmmm thats interesting. Im not sure, will have to look

[aragorn]

sounds like a faulty tank level sensor to me

[S3 Paul]

Mine got stuck once , But after changing the pump ( inside the unit with the sender on) its been fine

[Alais DJA]

Fuel pump lag - there was a similar issue with my mates 1.8t golf.

Uprated the pump, new sensor, and fuel filter. Dumped a bottle of red-x in it. Perfect ever since

Marcus