Fuel guage reading wrong

[TSport_Lolf]

Hello,

Whilst driving today my low fuel warning indicator pinged up unexpectedly telling me to fill up, however my fuel guage is still reading that there is just under half a tank left. Having checked the range on the trip computer this seems to confirm that the computer is saying as I only have 25 miles left.

Which one is most likely to be wrong and how can I go about having the reading calibrated correctly?

Thanks,

Lolf.

 

[wibble111]

Could be the sender unit in the tank itself. Easy enough to get at, under the rear seat bench is a cover, sender unit inside there IIRC. Make sure its well ventilated before you do it and dont smoke

 

[wibble111]

Forget that last post only just read it properly, not heard of that one mate so not much help dude.

 

[TSport_Lolf]

It actually seems like my electronic trip computer may be out by some margin. I filled my tank up last night from when the trip told me I only had 10 miles left, however the car only took 45 litres to fill and considering they're 55 litres in the Audi, this seemed to tally right with what the guage was saying at just over a quarter of a tank. Where does the trip computer get its readings from?

Thanks,

Lolf.