Fuel tank range extremely low

Put my second tank of gas in the truck last night, I got 22.79 mpg between fill ups which is fine because I did a bunch of around town driving. However, when I filled up the truck said I had ~115 miles of range left but it only took 11.1 gallons of gas. This clearly means the range is being super conservative as 7*22.8~= 160, so why is it reading so low? Is this just something I have to get used to or can I reprogram it? This could potentially be a wheel size issue, SRs come on 245/70R17 so perhaps the wheel diameter is too small?

 

The onboard computer sucks at prediction.

 

Do real math by hand for a few tanks so you know what's actually happening.

Suspect you'll find that the automagic stuff will become more accurate with more fillups.

If it doesn't, you'll have your hand calculations to show the dealer for your warranty work.

BTW, my WAG is that 22.79 with a lot of city driving is optimistic. That's in the territory of our '14 RAV.

 

Truck says like 360 on a full tank which is nuts to me

That mileage split is from ~220 miles of highway driving and ~30 of city, I was in some pretty short range drives between different stores though, and I don't know quite where to shift yet for optimal fuel economy I'm still getting used to the ratios on the transmission.
Hopefully this rangefinder calibrates soon, otherwise I'll just have to start saying "I know my truck" when the range has read 0 for 30 miles...

 

Doing the math is the way to 'know'.

 

Total side track here...

IMHO - The standard for vehicles sold in America "SHOULD" be (and I say that with enormous air quotes, underline, italics and bold) should be 400+ miles. This country has some wide open spaces in it.

So if you drive a Hybrid that gets 45MPG then you need a 9 Gallon Tank.
If you drive a Taco with a 20MPG rating (I'm not aware of a vehicle that is currently sold getting less than 20MPG) you should get a 20 Gallon Tank.

I used to drive a Titan with the 5.6. Great peppy little motor. But commuting to and from work required weekly fill ups. Like, fill up on Monday on the way in and then Thursday afternoon so you could get back on Friday morning. It was rated for 10 MPG and I was babying it to get 14. 40 Gallons is a lot of gas but that's what that Truck should have had.

Anyways... As you were. Thanks for the space to rant.

 

Personally I agree. My previous car is a BMW 325i, it got 28 mpg in the winter and 29 in the summer with a 16.7 gallon tank. I could do 500 miles on a single tank of gas if it was all highway, and I NEVER got less than 400 miles out of a tank of gas. The fuel gage estimated the range properly as well down to the last gallon. I have put 16.5 gallons of gas into that 16.7 gallon tank a few times!

 

400 miles at 22 mpg combined (sport, pre runner, sr5 2wd) is 18 gallons. 4wd is just under 19. We have an 18.5 gallon tank.

 

You have a 17-18 gallon tank. If you pumped 11 gallons that means you had 6-7 gallons left in the tank. 6 gallons of gas @ 20 mpg will take you 120 miles. Your onboard estimate of 115 miles is pretty accurate. More accurate than most. You will have about 3 gallons left in the tank when the gauge is on "E" and the low fuel light comes on.

Personally I never look at those things. They use the fuel mileage over the last few miles to try to predict your fuel mileage in the future. The road and traffic conditions ahead of you may be very different.

 

If it is like 3rd gen Tundra they keep a ridiculous reserve. On my 2023 Tundra the low fuel light comes on and remaining range goes to zero with 6 gallons left (out of 32). I guess they make it that way in case you are towing heavy and getting single digit MPGs.

 

Good to know, I'm not used to having a car where "E" isn't actually empty, made me worried there was something up with my fuel economy.
Now that I think of it, my parents had a 2007 Lexus RX350 that had a similar capability to run on "E" with reserve gas, I remember my dad driving for like 35 miles to the next station like that when I was a little kid. Must be a Toyota thing to do the gages like this

 

Your truck should not be indicating E if you still have 7.1 gallons in the tank. Either what you reported is incorrect, or your truck has a defect.

 

On a few rare occasions I've coasted in on fumes with 0 or damn near 0 miles to E and put in 2 Gallons more than the stated size of the tank before it clicked off the first time. And coming in on fumes you know I went to a second slow click to make sure it was full. I reasonably assume that most tanks would then have 2 gallons in reserve. That gives you about 40ish miles to find gas.

 

I was not on E at fillup but it was reading about slightly over a quarter tank

 

I drove my truck, down hill, for 10 miles after seeing "0" miles to go. Truck took 2.5 gallons. My 2nd gen had 3 gallons left after burying the gage on E. So about the same except one truck being analog and one being digital.

 

yeah it totally is a Toyota thing. As you know reliability is their brand. So they help prevent wear on their submerged fuel pumps, making them more reliable, by encouraging you to fill up before it gets too low… and optics to reduce the number of Toyotas on the side of the road because of drivers running out of gas

 

Also remember that 0 on thr distance-to-empty gauge is when they want you to fill up, not necessarily when you're out of gas.

In the 4Runner, 0 on the DTE gauge means 3 gallons left, and the light comes on 1 gallon earlier.

Sounds like it's working properly, within reason. Apparently (due to the posts on here), the auto MPG and DTE sucks when the car is new. I bet after 5 tanks or so, the truck will get better at predicting range, and you'll get a better idea of what the numbers & gauges mean (for your driving style).

I still do the motorcycle trick, and reset the trip gauge every time I fill up. Then I can reconcile miles at 1/2 tank, and figure where I'll end up. The DTE gauge moves around a lot over the course of a tank, so you know it's just a best guess.

 

I'm getting about the same range as I did with my 3rd gen. But they need to do a software update on the estimated range.

 

Was surprised to read the gas tank shrunk!

https://www.torquenews.com/17612/af...toyota-tacomas-tank-size-which-forces-me-stop

 

35” tires…