Fuel gauge with a mind of it's own...
 

Hi,

My A8 has a bit of a fuel gauge issue after it gets below between a half tank and a quarter tank - it basically sits there for ages, then drops down to empty, and then moves about and obviously is very untrustworthy at that point.

Is it just a sensor issue?

Thanks

Well, new cluster 100-135 pounds ! so wouldn't start there

VCDS would be where I would start unless its one of the odd common issues with D2s known to other D2 owners in here

Don't know what to say more really

You might have a problem with your fuel pump or its installation.

The fuel tank is basically two halves, well not quiet halves. When the fuel drops to a certain level the car starts to pump fuel from one side to the other so the pickup has enough fuel to run the car. That level is between half and quarter somewhere.

I do know that if the pump is improperly installed, when you get to that key point then the engine usually stalls because it runs of of fuel even though you have loads in the tank.

Could just be a problem with the sender as well, its easy to get to and check. Remove the boot carpet, and you'll see a metal plate to the rear on the right hand side. Remove the screws and the cover, and you'll see the fuel pump and the cap for the sender.

Have a read of my thread below where I had to take it apart to fix a seal, it has some links and several pictures on how to access the sender.
http://forum.a8parts.co.uk/showthread.php?t=4645

Thanks for the advice, it doesn't stall or anything, and it doesn't feel starved of fuel or anything when it's below that point which makes me think it is more likely to be the sender. I'll have a look and see what happens.