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I'm now on my second tank of gas with my new XV and the computer is giving me just wacky read outs that don't seem to reflect my actual MPG.

I am 20 miles into my latest tank of gas, I reset the trip computer immediately after I filled up. The fuel gauge still shows as a full tank (which is reasonable, since the last tank was manually calculated to give me 25+ MPG). However, the in-dash readout is saying I have 260 miles of gas remaining (can't be right, it said something like 380 right after I filled up) and that I am averaging only 15-16 MPG (also can't be right, since I don't believe I've even used a gallon out of the tank yet). The computer was within 1 MPG of actual MPG on my last tank of gas. What the heck could be going on here? Could I have set something incorrectly when I reset the trip read out? Worth a dealer service visit? Or wait and see?
 

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I have 140 miles on mine. Doing the same thing. Probably still learning driving patterns, etc me thinks.
 

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I feel like I noticed the same thing at first, too, but I was resetting the trip every time. From what I understand, this resets the computer MPG gauge every time so it has to relearn your driving style all over again. Maybe don't reset the trip the next tank and see if the numbers begin to start averaging out better.
 

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I now have over 8,700 miles on my XVC, I reset the trip computer after each tank and for the first few miles of the tank, the MPG is showing an average over a very small sample set. As you drive more, you will see that the MPG will regulate closer to what you are going to average.
 

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Chuck said:
I now have over 8,700 miles on my XVC, I reset the trip computer after each tank and for the first few miles of the tank, the MPG is showing an average over a very small sample set. As you drive more, you will see that the MPG will regulate closer to what you are going to average.
Yes, this!
 

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Reset trip A every fill up but leave trip B for longer periods, I usually reset it when the oil is changed. This gives me a long sample range for different things and is pretty much a dummy proof way to remind me to change the oil. Me being the dummy :D
 

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gravitylover said:
Reset trip A every fill up but leave trip B for longer periods, I usually reset it when the oil is changed. This gives me a long sample range for different things and is pretty much a dummy proof way to remind me to change the oil. Me being the dummy :D
Good advice, I do the same.
 

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I may be able to shed some light upon this subject. The first three view options are as follow: Miles until empty, Average MPG, real time MPG. Now with that being said there are two things that will effect these they are called short and long term fuel trim. Im not going into detail upon this because its a pain lol. Now then your miles until empty will not reflect your MPG because it will run off your long term fuel trim meaning it will become accurate as you drive it. Your average MPG is affected by both but is touching especially after a fresh reset. Your real time MPG runs only off your short term fuel trim. Now long story short when you reset trip A or B it will become more accurate as you drive. Basically long term fuel trim gets info from short term and does like a ga gillion mathmatical equations constantly. I hope this helps.
 

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Actually, when you have time, a detailed explanation of long term vs short term fuel trim calculations would be good to read and learn about.
 

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Lol I would recommend you google or wiki fuel trim and it will go into deep detail prolly even in words for those not mechanically inclined. But I appreciate your enthusiasm to learn!
 
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