help me calculate my MPG
02-26-2013, 04:02 PM
#1
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Year: 1989 2 door
Model: Cherokee
Engine: 4.0
help me calculate my MPG
my speedo is off by 4-5 mph.. how do i know? when my speedo shows 65 mph my navigation shows 70 mph... is not as bad at slower speeds about 2-3 mph off
on the last fill up i timed my trip odometer thingy and i got 221 miles and when i filled up it took 16.6 gallons so 221 divided by 16.6 = 13.3 mph...
but my speedo is off and i cant figure ou the formula on how to get the real MPG
i am running 30 inch tires and wondering what do i need to do to make my speedo accurate? is there a sensor to replace?
on the last fill up i timed my trip odometer thingy and i got 221 miles and when i filled up it took 16.6 gallons so 221 divided by 16.6 = 13.3 mph...
but my speedo is off and i cant figure ou the formula on how to get the real MPG
i am running 30 inch tires and wondering what do i need to do to make my speedo accurate? is there a sensor to replace?
02-26-2013, 04:20 PM
#2
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
02-26-2013, 07:39 PM
#3
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Year: 2001
Model: Cherokee
my speedo is off by 4-5 mph.. how do i know? when my speedo shows 65 mph my navigation shows 70 mph... is not as bad at slower speeds about 2-3 mph off
on the last fill up i timed my trip odometer thingy and i got 221 miles and when i filled up it took 16.6 gallons so 221 divided by 16.6 = 13.3 mph...
but my speedo is off and i cant figure ou the formula on how to get the real MPG
i am running 30 inch tires and wondering what do i need to do to make my speedo accurate? is there a sensor to replace?
on the last fill up i timed my trip odometer thingy and i got 221 miles and when i filled up it took 16.6 gallons so 221 divided by 16.6 = 13.3 mph...
but my speedo is off and i cant figure ou the formula on how to get the real MPG
i am running 30 inch tires and wondering what do i need to do to make my speedo accurate? is there a sensor to replace?
Frankly, 14 mpg stinks for any Jeep. My stock 2001 Sport averaged 23.2 mpg at the last fill. We don't baby it --full throttle, smokey-tire launches off the line happen now and again. And we do a LOT of city driving. And at 152,000 miles, it looks and performs like new.
And I plan to be buried in it in about 30 years.
02-26-2013, 08:06 PM
#4
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Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
Another option is to use the county mile markers and compare that to your odometer. I'm not sure how accurate they are so I did a few of "samples" of 15-20 miles and averaged it out. (and samples within those samples). My 235's seem to be 5% over the stock 225's, so I add 5% to my miles before dividing.
5% is 2-1/2 MPH at 50. I cover a mile in a minute if I hold it on about 57, so I think I'm pretty close.
5% is 2-1/2 MPH at 50. I cover a mile in a minute if I hold it on about 57, so I think I'm pretty close.
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