How accurate is miles left in the tank?

[Fred Leeson]

I'm nearing the end of my first tank of gas. With the needle showing tank at 1/4, the "miles left" says 150. How accurate is that reading...or how accurate is the needle?

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[CometGT]

Can't say how accurate, since I haven't run out, yet. However, the manual states (for the hybrids) that if you do run out, you need to put in 1.5 gallons before trying to restart it. The number of gallons I have put in it at fill-ups seems to agree with a 13.5 gallon tank combined with the miles driven.
So, advice for hybrid owners is to never let distance to empty get below 60 miles (1.5 gal @40 mpg)

 

[Derwood]

I'm nearing the end of my first tank of gas. With the needle showing tank at 1/4, the "miles left" says 150. How accurate is that reading...or how accurate is the needle?

Best advice I can give is to not let your tank even get that low. Makes your fuel pump work harder.

 

[d7602002]

Best advice I can give is to not let your tank even get that low. Makes your fuel pump work harder.

I was always curious as to why they said don't let your tank get too low. My father always used to just tell me keep it above half. Never knew why, just figured he was probably smarter than I was so i never questioned it.

 

[HeyBales]

Not accurate at all as far as fuel level.
1/4 needle is well above 3.5 gal.

Stated miles to empty totally depends on what you have been observing at the end of each trip when you stop. If you want fail-safe than use 3.5 and that figure.
Mine was no where close on 1st tank despite system knowing what my avg trips had been for mpg.
Of course it doesn't know if future trips will match past trips. (sounds like financial disclaimer)

My fillup gallons to 2nd click after a pause, since Apr. 600 miles or better on each tank.
14.6
15.1
14.4
15.0

ETA:
Now that you have a thread - go read the threads about over 600 miles or others about hybrid tank size - it's been proven it's over 13.8.

ETA:
In each case of fillup - I was 10-50 miles past the 0 to go mark (wanted that 600!). Needle does go below empty, and it was barely below in each case.

 

[HeyBales]

I was always curious as to why they said don't let your tank get too low. My father always used to just tell me keep it above half. Never knew why, just figured he was probably smarter than I was so i never questioned it.

One reason was dirt in bottom of tank, because of dirt in gas station tank, and not greatly sealed fuel systems. Much of that got changed thru the years as sealed vehicle systems became a requirement, same for station tanks.
Still could get some stuff on the bottom, which would just clog filter faster. And if filter was after the pump that would be a negative for the pump too.

Other reason was when pumps were put into the tanks - that was how they were cooled.
Gas would transfer heat off pump better than air. Then again pump was usually at top of tank, and fuel was rarely at tip top. So more a matter of mass of cooler fuel than air that could change to ambient air temp quicker. Of course fuel eventually will get to ambient air temp too - but still cooler than long-use working pump.

Other reason for avoiding running dry was when pumps use a diaphragm style mechanism - with no fuel providing pressure on one side of the diaphragm, over-stretch and faster wear would be a problem.

So some of those things for sure changed thru the years.
And people can avoid gas stations that look iffy for their general cleanliness (which could indicate likelihood of dirty tanks), and probably not carrying top-tier fuel anyway.
Filters are before the pump now - in tank at bottom so bigger expense to deal with, but can keep pump in better shape.
Hybrid fuel pump cooling perhaps not a big factor unless highway speed actually running constantly. Otherwise just not running much.
Not sure how hot current fuel pumps actually get - maybe cooling not a factor anymore.

But it does seem people totally running dry (or least when pump cannot reach it) frequently do seem to ruin their pumps more.

 

[Scott Asheville]

I've run mine down to 15 miles indicated before I lost my nerve.

 

[surfstar]

Go past 0 and you'll be fine.
I've put in 14.5 g a couple times - and not overfilling / extra clicks.

So much old info in this thread so quickly. Fuel pumps don't die if you refill when the light is on each tank. Never happened to any of my vehicles or families'.
Gas pumps have filters. When filters get clogged, they filter BETTER, but flow slower (unless they have a bypass). So unless the station replaced them with no filters, almost every single station is filtering the gas through the dispenser when you fill up.

Lets talk about first oil changes and "break-in" - that'll produce equally valid discussions.


To get back to the OP's question - figure it's accurate +/- 5%
Remember that it will drop faster or slower depending on your mpg over the tank and final 1/4 tank. So it has to be a rough estimate. You might have been on the hwy then more city miles or vice versa - that is like a 20% difference in hybrid Mav mpg, so it can vary greatly.

 

[AVC]

Ran mine below "0 miles"multiple times; 25 to 40 miles "negative". Took 14.5 or so gallons before first click.

 

[2seater]

The only way to determine how accurate YOUR gauge and estimates are is to drive it and refill the tank at various points. Keep a record, at least for a while, and hand calculate. I find the total of miles driven plus left to go, added together, is somewhat more accurate than the stated MPG, but is generally optimistic by some percentage. I also find it gets more accurate on extended trips rather than the sum of multiple shorter trips. Just my opinion.

 

[The Real Maverick]

It tells you miles to empty = 0 after you have burned 13.8 gallons.

But the HYBRID Trucks hold 16.5 gallons.

So at "imaginary computer calculated pretend empty" you still have a lot of reserve and you still have your fuel pump covered with fuel. (The fuel pump is also in a special deep pocket "sump".)

Toyota got sued for having tanks smaller than advertised.

Ford went the other way and installed tanks larger than advertised. In the EB too.

So 13.8 is the normal, expected, repeatable fuel you can use every time.
It holds 16.5.

EB (I don't have one) but I've seen people add 18.5 gallons.

 

[mr mojo risen]

EB (I don't have one) but I've seen people add 18.5 gallons.

I have been recording my odometer, total gallons, and miles traveled between fill-ups since I bought my Maverick. I’ve run past zero maybe twice; only when I know I’m close to multiple gas stations.

The most I’ve put into my gas tank is 16.84 gallons.

 

[dogtruck]

A man never knows his limits...until he has exceeded them.
All advice previously posted is good, but sometimes ya just gotta figure things out for yourself.

 

[raymaines]

I was always curious as to why they said don't let your tank get too low. My father always used to just tell me keep it above half. Never knew why, just figured he was probably smarter than I was so i never questioned it.

I think it's all about your risk tolerance. I'm not comfy at less than a 1/4 tank but maybe you're the guy that gets a weird thrill running on fumes just to see how far you can push things. "If ten will kill me, you can give me nine." My brain tells me I don't get bonus points or a discount for running on empty, and the "next" gas station is always the most expensive one in the county. Fill up early while things are still semi-convenient, you really can't beat physics.

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