Agreed!!! The longest gap for me going to Cali is only 126 miles between service station. Which is a little over half tank. Nothing to worry about gas wise but I get road rage when I'm hungry. lol

 

yet I can only fill up 17.5 at most.

 

But were you empty at the time . . . or did you still have 2-1/2 gallons left in the tank?

If you are going by the gauge and 'mileage remaining' indicators, they are calibrated to provide about 2-1/2 gallons remaining in reserve beyond zero.

 

Yes true about the reserve... To be honest I was pretty darn low reading "- - - -".
There has been once i can recall I was able to force 18.
I generally don't like to run on empty for too long, because of things I heard about sludge
Entering into parts of the engine more easier when at the bottom of the tank.

 

I put in 17.5 gallons about 10 miles after the "----" warning. But the range didn't show single digits, it dropped to "----" after the last range displayed was 15.

I had a range of about 35-40 once and redlined the car in 2nd gear and the range instantly dropped to "---" and stayed there until I filled up, so aggressive driving can throw off the calculation.

 

I've been wondering when the low fuel light comes on. I watched one day. I've been averaging about 20mpg, so I planned to go 40 past the light. It came on at 335, so I drove to 375 and filled up. It took 18 gallons to fill it. So I could have gone to 405.... in theory. So I ran the average it was right on 20.8. This backwards math tells me the light came on at 4 gallons left, the needle is at E. But at E, I really have 60 to 80 miles left. This is based on an 06 sedan non sport auto. My daily route is about 30 miles round trip, 65% hwy. The 'city' part is still about 45 speed limit so I'm not really sitting in traffic much.

 

^^ your first gen sedan may be slightly different from the 2nd gen sedans which typically have a 2.5 to 3 gallon reserve once the trip computer says you're at " - - -" miles

 

I started the trip odo when I reached the "---" and was able to go 36.8 miles before I felt the car drop idle lower then normal, got scared pulled over and put gas in that I brought. I drive a 2008 X and did mainly city driving about 35-45 mph with not too many stops along the way. So when you reach "---" I'd say you can safely drive 30miles to find gas before shutting down.

 

Once I drove about 35 highway miles after the "---" came on before i filled up. I was only able to put in 18-something gallons.

 

I've gone over 45 miles. When I filled the tank later, the meter read 19.9x gallons.

 

all I can tell you is, You keep running on fumes you will be needed a new fuel pump very soon. lol.