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Discussion Starter #1
ok has anyone had theres actually be close as in .1-.4 from actual mine reads low surprisingly not high all my hand cals are with full tanks fuel visible in the neck and i have done the speedometer correction math for oversized tires and mine reads about .1-.4 mpg low just wondering if anyone had something close
 

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mine is usualy .3 high
 

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If I do all steady driving, mine can be quite accurate. As soon as start doing stop/go type stuff, it can get as much as 2 mpg off.
 

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I'm not sure why, but mine reads 4 mpg high all the time. I have adjusted the computer for larger tires too.
 

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Mine is waaaayyy off.. Hand calc i get 15 or so.. Lie-o-meter currently says im getting 24.
 

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Mine reads anywhere from "Dead-on" to 1 mpg low so I always know I'm at least as good as the OH is showing....
 

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I have also found mine to be dead on most of the time when compared to my hand calculations. About the speedometer correction...I've had bigger aftermarket rims and tires for almost 2 years and have never had the dealer adjust my speedometer. However, I have my rim and tire size saved on my PMt so I get my MPH off that but my speedometer is always 2-4 mph higher?

what gives lol

Thanks
 

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I reset mine everytime I refuel along with my tripometer. Its usualy between .5 and 1mpg high.
 

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the less torque management you have with whatever programmer and/or the bigger the injectors, the more the mpg calculator will be off.
 

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Mine is way off, high, last tank hand calc I got 16.84 mpg all town driving and the lie-o-meter 23 mpg, so that means it was off by 6.16 mpg. I have larger tires and wheels and I reprogrammed my stuff with my Jr. and checked against my gps and I am pretty much on the money between the speedo and gps.
 

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Mine reads the other way than most of you guys are posting. It will say 16.2 and I will be getting 18.5.
 
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