Gas Mileage Inaccuracy

My fuel mileage app says I am getting 28.8 mpg. But the actual is 20.8.
To start, I filled up, I zeroed out the mileage app and updated it, and reset Trip A to zero.
Awhile later I filled again, 13.1 gallons.Trip A says 269 miles.

 

Are you still running stock size tires?

 

Measure your tire circumstance.
Perform measured 10 mile check at 60. Three times. Using two measurement tools.
Calculate factor.

Fill tank. Drive tank. Three times.
Apply calculated factors.
Correlate to the inaccurate monitor.

 

Friday response to a message 1 op troll.

@whatstcp 5000 high quality posts at that!

 

Oh absolutely, but it was well thought out. +1 for you sir

 

Thank you.
Our nation needs more wit.

 

5000 posts...

 

Mine was a consistent 0.5mpg high on the computer side. It was not a big deal, like yours is. Once I did the DTC and LV Resets, it was either right on or within 0.1mpg for a long time. This can be done within TechStream.

Now, it is off about 0.3mpg. Still, very reasonable to live with.

 

Damn, im still a little puppy...

 

Welcome to to the forum

Mine is inaccurate too. The best way to calculate true mileage as you described. Use the trip meter and record how much fuel used for distance driven.

 

Mine was corrected by adding 265/75r16. Now it's dead on. I average about 15mpg. I drive like I stole it sometimes.

 

I'm too lazy to check and see if this is possible on the Taco, but on my Volvo XC60 you can set the mpg to read miles per Imperial gallon. It gives a result similar to what you describe since an Imperial gallon is 5 quarts or some such thing.

 

Toyota told me they would not adjust it is just an estimate. The only thing close to accurate is the odometer mileage.

 

What is a tire circumstance?

 

I think how much pressure is in the tire?

 

Oh no. Not the flat spot.