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Me and the wife have noticed that the gas mileage hasnt been counting down correctly I guess you could say, we had 40 miles left to empty and clearly went almost 50 -60 miles before stopping for gas. Has anyone else had this issue before?
 

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This is discussed in threads elsewhere in the forum including the fuel economy area. The "miles to empty" is not linear. it's based on the running average for the currently displayed trip computer and it can change based on how the vehicle is being driven "now". It may go down slower or faster and it may even increase if one starts driving in a more efficient way, such as on the highway.

IE...this is not an "issue".
 

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It also increments up or down in even 10 mile boundaries, not individual miles.
 
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Yeah. The range after the fuel light comes on at a range of 40 miles bounces around going up down to -- and back up as much as 30 miles. One fillup, the range displayed was 770 miles! It's funky.

My previous vehicles (Lexus, BMW, Audi) had much more usable range gauges. The way the worked, apparently, is the range displayed was always the tank level times the a default mpg. If you were using fuel more slowly, the displaye range would decrease more slowly, but was always based on fuel level times the default mpg. As such, the displayed range only decreased. With this system, I could better anticipate my fuel stops. I can see how the Ascent range works, apparently, fuel level times the very recent mpg, but I find that less useful.
 

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I find the Ascent's very useful, with it's Miles Remaining recalculation based on (some sort of) aggregate recent mpg. If I am driving conservatively to eek it out to the next gas station, I think it's dead-on correct that the car adjusts its estimate based on my new hyper-miling right foot. Results in the best information, at least in precision of estimate. But it does jack the number around a bit.

Other cars (I drive a lot of rentals) don't do this, or soften the recalc. Maybe it's because when they tested the aggressive version of the feature, people threw up all over it, and their marketing departments decided to give consumers a dumbed-down steadier readout. Subaru, on the other hand, is treating us like the smart consumers that we are, and giving us the raw stuff. IMO.

(Wish Subaru would do that more consistently and kill fake shifting... oops did I say that?)

A separate consideration is how much headroom the Ascent leaves at the bottom. When it finally hits zero miles left, there's still a little reserve left. I've driven past zero many times, but usually not by many miles.

One more separate consideration is how much gas the tank actually holds, or rather, fills up with when depleted. I've not run out of gas (yet), but on two occasions, I've gone 20 miles past 0-miles-remaining, and the pump stopped at 18.5ish. Not even close to 19.3! In one case, I kept pumping past my usual two extra squirts, just to see. The pump hit 19.1 and the filler overflowed. (My apologies to the environment.)

TMI.

F.S. (2019 Touring)
 

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I kept pumping past my usual two extra squirts, just to see. The pump hit 19.1 and the filler overflowed. (My apologies to the environment.)
Just so you know, while overflowing the tank is certainly no bueno for the environment, you also run the risk of damaging the evaporative emissions system when overfilling. That's the main reason you're not supposed to top off anymore.
 

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I find the Ascent's very useful, with it's Miles Remaining recalculation based on (some sort of) aggregate recent mpg. If I am driving conservatively to eek it out to the next gas station, I think it's dead-on correct that the car adjusts its estimate based on my new hyper-miling right foot. Results in the best information, at least in precision of estimate. But it does jack the number around a bit.

Other cars (I drive a lot of rentals) don't do this, or soften the recalc. Maybe it's because when they tested the aggressive version of the feature, people threw up all over it, and their marketing departments decided to give consumers a dumbed-down steadier readout. Subaru, on the other hand, is treating us like the smart consumers that we are, and giving us the raw stuff. IMO.

(Wish Subaru would do that more consistently and kill fake shifting... oops did I say that?)

A separate consideration is how much headroom the Ascent leaves at the bottom. When it finally hits zero miles left, there's still a little reserve left. I've driven past zero many times, but usually not by many miles.

One more separate consideration is how much gas the tank actually holds, or rather, fills up with when depleted. I've not run out of gas (yet), but on two occasions, I've gone 20 miles past 0-miles-remaining, and the pump stopped at 18.5ish. Not even close to 19.3! In one case, I kept pumping past my usual two extra squirts, just to see. The pump hit 19.1 and the filler overflowed. (My apologies to the environment.)

TMI.

F.S. (2019 Touring)
I finally figured out that I can carefully add gas when the pump stops and will take just about two extra gallons,
which can improve the range from 350 to about 400 miles on a 65-79 mph interstate, even on winter gas.
I have to put my head close and "listen" to the gas pump but I have learned to do this without it spilling.
On an "empty tank" it will take over 19 gallons but you really have to be careful at that point it doesn't go over.
 

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The tank and filler are designed to leave some air space at the top of the tank when filling normally to allow for expansion of the gas. Unlike water, gasoline expands a fair amount when it heats up and it usually comes out of underground tanks being reasonably cool and will expand in warmer outside temps and from engine heat while driving. If you fill the tank completely full with cool gasoline and it expands, some can be forced out and adversely affect the evap control system, as has been mentioned.
 

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Also the consensus is that on Subarus, miles to empty actually means something like there’s another 50-70 miles on reserve after “empty”.
This makes sense for everything I have noticed. I have owned my Ascent for a year and keep noticing that when I fill up, after it says I have about 60 miles left in range, it'll only put between 15-16 gallons in. I kept thinking how off my needle must be but when I calculate another 50-70 miles in the reserve, now it makes perfect sense (assuming your information is accurate and true).
 

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My impression is that miles to "empty" means miles to "the safe point where the gas pump is still immersed". Most modern day gas pumps are lubricated by the gasoline, so, running them dry can burn them out. Late 80's Range Rover fuel pumps were notorious for that. I burnt out mine the very first time I ran out of gas. That cost me $700 to fix.
 
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