Distance To Empty (in)Accuracy

As I pulled up to the gas pump, the distance to empty changed from "1" to "Please Refuel". Even with "topping off," it only took 18.5 gallons. Since the truck has a 21.1 gallon tank and I've been averaging ~18mpg, the DTE is off by over 45 miles. Is this level of accuracy typical?

 

May be just a computer being a computer. Your float looks good still above 'E' but I am no mechanic.

Do you do your own calculations after fill up or just go by the screen?

 

I've never had the guts to test it that low. Maybe it's programmed a little on the safe side so people think it's lower than it really is?

 

That about what I put in each time I fill up.

 

It's off in the T4Rs I've owned. I really watch my MPG and I measure how much fuel I put in so I know how far I can drive since last fueling. Mine will show 1 mile remaining and can/have driven it an additional 18 to 20 miles...even though I prefer not running that low.

 

I've been relying on the displayed average so far, but regardless of the mpg accuracy, it's off by ~2.5 gallons.

I figured it would err on the safe side, but it leaves over 10% of the tank's capacity when it says it's empty.

One of my father's previous vehicles would actually run out of gas shortly after the DTE hit zero.

 

Mine once said 415 miles until empty as opposed to 385 like it usually does. I figured it was a glitch but maybe that's it's true number.

 

Maybe it uses the average of the previous tank?

 

I assumed this was done to error on side of caution to the driver, and so not to damage the fuel pump by running to low? Is that still a thing, I was always told that fuel pumps are lubricated by the gas and not good to run dry.

 

Last fill up said 422 and todays fill up said 392, must be working off some kind of average.

 

Well, back in my dirt bike days, this was called reserve...no guage on a dirt bike, so ya ran it til it ran outta gas (young, dumb and full of ... fun)...then you'd flip the fuel line valve to reserve, and you'd typically have 10% of your tank to go find more juice....

Now its called a 'puter, and people complain lol

 

It's a reserve to keep from Running dry not to Damage the fuel pump, Same way it's ben in my previous Tundras...

 

I had a '69 Beetle that had an R instead of an E on the gauge, took me a while of wondering about it before somebody explained that it was a carrier over from older beetles that had a reserve tank.

 

The manual says that there will be 3.2 gallons left in the tank when the refuel warning comes up.

 

I came here to post that.

You should have 45 miles (15mpg x 3 gallons) after the light comes on if you're being conservative to be 100% empty. I usually fill up 30-35 miles after the light comes on.

 

My second gen just has the idiot light - which comes on with about 3 gallons left.

 

My 07 had the same thing.

 

Toyota loves a reserve when the light comes on. Usually can get an extra 100kms once the light comes on.

The best way is the old school way, watch KM's (or miles) and jerry can fill once its dead.

 

No.

From google (which can explain it better than I can in a user post; this is not "scientific" just a general explanation):
"
There is lots of "urban legend" stuff surrounding this subject.. In most tank / pump designs, the actual pump is mounted high in the tank and is only submerged when the tank is full or nearly so. Since the fuel system constantly is returning excess fuel to the tank in a closed loop constant pressure system, the fuel flowing through the pump keeps it cool, if indeed it needs to be kept cool..This whole argument depends on the fallacy that in-tank fuel pumps are somehow subject to overheating when in fact I don't believe that's the case...

Overheating fuel pumps inside a closed gasoline tank are NOT a design feature that is built into these pumps. They don't fail because they overheated. They fail because they wore out or the flex-lines that connect them inside the tank rupture and pressure is lost. Once fuel pressure is lost, the engine and fuel pump are shut down long before the pump "burns up"..."

 

I thought they did away with return lines a few years back and designed returnless style systems, maybe Toyota still does return style still though.