That was easy!
The fuel gauge on these cars is somewhat unreliable
. A little German quirk. Sometimes it sticks at full, sometimes the float gets soggy and never really reads full (mine). You can change it out but the word on the street is that the new ones aren't much better. To overcome this I just reset my trip log at every fill up. Once I log about 250 miles I know the gas gauge means business. Time for gas.
You would think they could figure out how to solve this simple problem.