I have noticed that my fuel gauge, 2005 S4, is not displaying correctly. I can have 100 miles on the trip meter and it will register as 3/4 full when I start it, then after 15-20 minutes of driving it will register full and stay there. Later it will drop down to 1/2. I've had a couple of issues where it was reporting 1/4 full and the engine starts running rough. Luckily I've been close enough to a gas station to fill it up and it starts running normally.

I read that it could be that the sensors are getting corroded and most people use a couple of treatments with Chevron Techchron to clean it up or take the sensors out and use an eraser to clean off the corrosion.

Has anyone had that issue on their Audi?

I was reading this thread on the fuel system cleaners, https://www.audiforums.com/forum/sho...d.php?t=149198 and saw some good recommendations on products.

 

Yep probably a hundred or more past threads on here - the search feature will reveal all.