Distance till empty is inaccurate.

Hello, I have a 2018 and have been pulling my 5th wheel and notice that the miles till empty is off. We have run over 6 tanks of fuel while pulling so the miles per gallon is reading correct at 8.6mpg. When it shows 100 miles till empty we can go 60 miles if we push it. Is there a way to adjust or correct the reading? Thanks

 

Guys, it's because your gas pump is located in the tank, and needs to be covered in gas. So when you see 0, you're about to go below that.

 

Yup, exactly. That reserve to keep the pump covered though-- so best to treat 0 as almost real.

 

Thanks for the replies. I know about the reserve after gauge reads empty. What I'm asking is why is the range till empty function so far off? It has to be a calculation of gallons till empty multiplied by the average fuel mileage. I've been averaging 8.5mpg for 2,400 miles so it should be able to display an accurate distance till empty.

 

So, what you're saying is when the truck calculates the distance to empty, it thinks it's getting 14.2 mpg, when you know it's only getting 8.5 mpg from your pump receipts. (60miles/8.5 mpg = 7.1 gallons; 100 miles range/7.1 gallons = 14.2 miles/gallon)

I've run another vehicle out of gas once using miles until empty range. Too much black majic and uncertainties in the calculation to expect high accuracy. It should be closer than that, but it is what it is. Maybe your dealer can "adjust" it, but I doubt it.

 

Try resetting the average mpg

 

Not trying to discourage you, but your expectation may be high. For that whole average mpg/distance to empty calculation to work properly, I have found that you have to fill your tank every time until the gas pump shuts off...once. Then, to protect your charcoal filter, stop, don't top off.

If you disconnect your battery ground cable, you will zero the average mpg as @15whtrd suggested. It will start over from zero calculating a new average mpg. Expect your distance to empty to be way out of whack until the calculation settles out. He and I believe your truck is using an average mpg from early in it's life (pre-towing) to calculate distance to empty.

BUT, what I found after disconnecting my battery to upgrade to 2018+ headlights, the average mpg, which was steady at 16.5 previously, settled out at 14.5 afterwards. Do I think the truck is actually getting 2 mpg less because of the new headlights?...not a chance. But, then I never fill my tank completely full, and I suspect that has to happen for the calculation to be ballpark accurate. One of those numbers is bogus, and the only way to know for sure which is to hand calculate...which requires completely filling the tank.

My advice is don't fret over technology that isn't quite up to GPS accuracy. Do it the old school way: When the gage gets down to 1/4 or 1/8, stop for fuel.

 

We don't rely on it. I use the tripometer and make sure I stop before I go 250 miles which gives me a nice reserve if a station is closed.

 

Im going to agree with a few of the guys here also. Your truck may be reflecting the average mpg that still has a much larger accumulated miles compared to what you are currently getting.

You know, 50k miles under normal conditions getting 15mpg. New conditions, hauling ect, 6k miles getting 10 mpg. Just arbitrary numbers but it would probably take a lot more milage under the new conditions before there is a significant impact on the mpg average in total.

Then again, this might all be irrelevant because you've already did a proper reset and all that jazz.

Meh...

 

FAKE NEWS!

 

Wrong

 

You don't need to disconnect your battery to reset your mpg.

Just hold down the disp button on the steering wheel for a couple seconds. Op give this a try.

 

Teach us.

 

I'm the opposite with my 07, it is way too conservative. Just finished towing my 19' TT from Texas to Colorado and back. On the way back we were really trying to make Amarillo for a show in Palo Duro Canyon. I went from Espanola, NM to Amarillo, TX on one tank. I hit 0 DTE about 40 miles before Amarillo, and when filling up still had 2.5 gallons in the tank.

I figured this out when I towed my campter to Matagorda Bay, TX. At 2 miles DTE, I still had nearly 5 gallons in the tank.

This is causing me to stop and fill up unnecessarily. I could have made the coast and not wasted time filling up.

 

The fuel flowing through the pump is how it cools, there isn’t much heat transfer through the plastic fuel pump “module” housing.

 

Thanks fellas! I'll stop spread this wrong info. Love me some @ColoradoTJ. The guy drinks and knows things.

 

8 gallons of reserve

 

Does the tundra have a low fuel light? I have a 2019 and have at least 8 gal left when the read out says I only have 16 miles to empty. So technically with the mileage I get of 16mpgx8gal will take me another 128 miles if necessary. That's one hellva reserve.

 

Normal and commonly posted about here

 

Some of ya'll sound like "reserve" is a dirty word.

A favorite shared story with my son is being in the middle of nowhere in my old 86 4Runner, near midnight, approaching El Paso. Nothing out there but rock, dirt, and weeds if you need gasoline. Operators know that and raise their prices between Sonora and El Paso to astronomical levels. The last opportunity for "cheaper" gasoline is Sonora, and from there to El Paso was almost exactly the range of the 4Runner.

When the bingo light came on, the gage touched the "E" mark, my son reminds me that I uttered the memorable phrase "I hope the two gallon 'reserve' is there". It was, fortunately, but that tank was smaller.

 

The only thing that is more accurate than the miles till empty is your local weatherman.

 

Once I drive past the "low fuel light" coming on and I drive until it shows zero miles left I have filed up and had 5.8 gallons left.
Tank holds 38 gallons minus gas pumped of 32.2 gallons = 5.8 gallons left.

It's your decision from there how far you think you can get.

Bear

 

Thank you for the reply, exactly what I was looking for. I have never let the light come on which is why I asked the question the way I did.

 

Excellent GOT quote.

 

I don't think I have ever been below 1/2 !