Gas gauge still at "F" when it's plainly not.
 

Some posts have mentioned this before. I was driving on the first real open freeway + daytime + full tank of gas to start road trip since the vehicle (2013 Q5 Hybrid) came back to the U.S. from Euro delivery last month.

See the picture. The gauge is still just at "F." But then notice the trip meter at 121.0 miles that I had reset when I filled it at the roadside freeway entrance. Okay, I get that vehicles hang on "F" for a while, other Audi's included, but the math here says close to 4 gallons were gone by then. Plus, as a Hybrid the tank is also a little bit smaller than all other Q5's/SQ5's for some of the Hybrid electrics back there. I had been watching it around that 120 mile mark when it seemed like it was finally going to start to come down from the beginnings of a little movement I was noticing over some minutes.

The indicated MPG's were in fact quite high here over extended miles--the highest I've seen and my calc's to date say the display to actual delta may only average 1-2% optimistic on mine. Calculated ave. speed BTW for the same tank was 69MPH, and probably the only extended drive in a single tank I have done purely highway at generally similar speeds; there were also some unique to the Hybrid downhill "tricks" in here that extended the MPG's more during a 60 mile leg coming down from the mountains--at freeway speeds where EV function normally doesn't play in much.

In this tank run, I know the tank was well filled, but still that seems like an awfully big gap before it starts running down from full. The math here says it had burned 3.65 gallons, almost 20% of the Hybrid's 72L/19 gal. tank. Having seen other areas of the tank reading where it drops pretty fast, the gauge continues to seem pretty non-linear.

Saw this a couple years back on an Audi A4 loaner BTW where I began to realize it was supposed to come back "full," yet I had seen it drop below "F" almost when I drove off the lot. Hmmm, how many gallons did I really need to put in to get back to "F"? At these #'s it is like a $15 swing for the gallons in play at "F" to put it into a real world example of when it matters.

Yeap, same issue with mine, we have a funnel shape fuel tank. I usualy get about 200 miles from full to 3/4 mark then 100 more to half,[ for 300 at the half mark] then another 100 to 1/4 and after that is anyones guess, usually 50 miles if in the city.

I guess i have to get used to it.

This is pretty common, and that A4 that you'd had? Whoever had it before just put in enough to show F and not actually fill the tank. Very common tactic for rentals, too. F is more of an indication that you've got a bunch of fuel rather than actually being full, and the marks are just a gauge of how much more you have to go. Not sure why they do it that way (I can see having E not be "running on fumes" for safety reasons, but F being held so long on everything is a little odd -- but very common).