MPG reads incorrectly

[stlsailor]

I have a 2008 4Runner. The miles per gallon reading showing on the printout consistently shows between 1.5 and 2 mpg more than I am actually getting. It seems to me my unit must be defective, but perhaps that's as good as they do, however if that's the case, why bother? Does anyone have a miles per gallon reading on your vehicle that is accurate?

 

[RonMAIDEN]

It's normal since most gas calculators will be off a little and sometimes they will be right on but your driving conditions and actions will vary and it's hard for the computer to stay dead on as just simply calulating your own MPGs.

 

[nated05]

This is normal, I usually subtract about 1-2mpg from my display readout. Does the Stl in your sig. stand for St. Louis? Just curious.

 

[stlsailor]

St. Louis

Yes, the stl stands for St. Louis. I had a sailboat until recently, hence the name.

I wouldn't expect a completely accurate reading, but I'd expect it to be a bit closer. But at least I know mine is not defective, the manufacturing tolerance is just not very good.

 

[Uneek]

The general consensus is the MPG computer is about 10% optimistic. I think only a couple members says theirs is pretty true/accurate.

 

[A/V1]

I rarely even look at mine and normally keep it on a setting other than MPG (like outside temp). Maybe I do it so I don't have to see the gas mileage I'm getting...

Ignorance is bliss!

 

[nated05]

Re: St. Louis

Yes, the stl stands for St. Louis. I had a sailboat until recently, hence the name.

I wouldn't expect a completely accurate reading, but I'd expect it to be a bit closer. But at least I know mine is not defective, the manufacturing tolerance is just not very good.

Cool! Welcome! What dealer did you get your 4r from?

 

[stlsailor]

|| Cool! Welcome! What dealer did you get your 4r from?||

Jay Wolfe. We live in Ballwin, they're close.

 

[pipspeak]

Yep, folks have been saying for years that the computer is 5-10% out with mpg calculation. Mine is about 2mpg out on long freeway trips (shows me getting up to 23mpg when I'm actually getting about 21mpg) but seems to be more accurate when driving around the hilly streets of SF (when I get about 12mpg

 

[Kmvreter]

... Does anyone have a miles per gallon reading on your vehicle that is accurate?

I keep accurate track of my fuel mileage. The display is accurate over the long term average (no resets for over 6 months.) I've had actual pluses and minuses against the average depending on highway vs. city driving. It doesn't do any good short-term when reset tank to tank so I've given up on looking at it. I leave the display at the range setting.