18 VW Tiguan and 15 Honda Pilot seems with 1 mpg the few times I crossed checked.
How accurate is the indicated MPG in your vehicle?
- Thread starter AZjeff
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No coincidence in my opinion. I find that they are reliably optimistic by varying amounts among different brands compared to what is calculated at the pump.
Most of my cars have indicated 3%-4% optimistic; the most accurate have been the my F22 M235i and my W205 C43. On most BMWs you can access a service menu that allows you to adjust the computation factors, but the discrepancies never bothered me enough to do anything about it.
On my ‘15 F150 it’s typically about 7% optimistic. The mph calculation is adjustable on my generation of F150. Set to 930/1000, it’s usually, but not always, within .1-.2 mpg.
Our truck is as much as 10% optimistic, but with long trips heavy towing, it gets pretty close to actual. 300k miles on injectors likely means they spit more at idle and light throttle than the computer thinks. It scales back duration at idle to compensate but I don't think it's smart enough to know if it's due to load or injector map errors. Under heavy towing I suspect the error at low injection quantities gets lost in the grand scheme. 300k on injectors, I can't complain.
Our mazda will generally accept about two gallons of fuel after the first click. That level of variability makes it hard to compare calculated vs readout from tank to tank. You do a <10 gallon fillup and wind up with a >20% error...
Our toyota 2gr is spot on, within the noise of fillup variability.
My Golf GTI is right on the money.
Took a trip this last weekend and my calculated mpg was 29.7 and dash showed 29.8 Mazda CX5 at 75 to 85 mph.
Wife's 2017 Accord V6 is 10% optimistic.
My 2012 is consistently about 1 MPG optimistic, so it reports 15.9 when actual is 14.9. My '06 of the same vehicle was usually within a couple tenths of a MPG.
Mine is generally 1-1.5 mpg off.
My CX-50 is about 1-1.5MPG low. Constantly underrates itself.
Mine was off as it always stated 21mpg average and I hand calculated 20. I set tire size for vehicle and over last month it reads 20 mpg average.
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BMW is +\- 0.1 mpg if say half tank or more is filled.
Lexus is +\- 0.3.
Buick is way off, -2 mpg or so and the more is filled the lower the amount it is off, if we fill 19 gallons it’s maybe -1mpg.
Somebody out there knows how they are actually computing the fuel consumed. Because the Buick math is correct, just that the gallons consumed reading is always off, ie higher. If I blink my eyes incorrectly suddenly another 0.1 gas was consumed.
My buddy said Lincoln Navigator was way off to the negative too.
Lexus is +\- 0.3.
Buick is way off, -2 mpg or so and the more is filled the lower the amount it is off, if we fill 19 gallons it’s maybe -1mpg.
Somebody out there knows how they are actually computing the fuel consumed. Because the Buick math is correct, just that the gallons consumed reading is always off, ie higher. If I blink my eyes incorrectly suddenly another 0.1 gas was consumed.
My buddy said Lincoln Navigator was way off to the negative too.
Kias in sig, about 10% too optimistic.
Heh. That's the opposite of my CX-5, which is almost always overly optimistic. Its most recent track for the tank was off by something like +3mpg.
The random mixture of city and highway driving I tend to do throws mine out of whack, or at least that's my impression.
