MPG is based on an algorithm that NIssan does not publish. I believe that MPG and DTE (Distance To Empty) are related. The Factory Service Manual gives a more technical explanation. I have tested MPG on the highway at various speeds: the results are accurate and validate common sense; that is, the faster you go the worse the MPG.

 

^^^ this

 

That's how I found out how accurate mine is and how I calc DTE myself because of the crappy fuel guage

 

I did this same thing after i was told my DTE computer was ****, most accurate way of finding ur true MPG, even though my MPG calculator hasnt failed me yet

 

I treat the DTE computer as a novelty, accurate to the nearest 45 miles.

 

Just clicked over to the dte screen. It says 435 dte blinking however my gas light is on cause I didnt put gas in the morning. Something tells me its unplugged for it to tell me I have 435miles eith less than 3 gallons in the tank lol

 

i noticed that it doesn't take a huge amount of data for averaging so this doesn't work as well as i hoped when I did it. i find better results by resetting it when i am doing a certain kind of driving. for example:

-Long Freeway Drive
-Long Street Driving
-Mixed Street/Highway

that gives me a better idea of the average MPG for each of those scenarios

 

what i do is drive long distance in the early morning (to find good surf spots) so my Z gets constant speed so it gets about 24.3 mpg then i refill full see what the guage says, reset it and, so far ive beem getting 425 per tank with chill driving, and smetimes getting sideways for a few minutes. Idk but works for me. When it comes down to it. I love my lol

 

I just checked mine from a full tank all the way to "---- DTE" and was only .1 off on the MPG, i reset my ODO and my MPG every time i fill up (VQ35HR)

 

I've had an '03 Performance for about 8 months now, and have only remembered to reset mine at refill four times now. Those four times it read high by 5.43%, 8.54%, 7.75%, and 6.55%. That's quite a variance, so I was surprised at how many people have reported it is very accurate for them. Wonder what the difference is.

I'm also fairly sure I'm plagued by the common fuel level sensor problem, as my DTE gives me a somewhat accurate number after I fill up when compared to how far I can go on a pretty good fill, but once the tank is getting low it freaks out way too soon, shows me ----, and I only get 13-15 gallons in the tank. :\

 

My 08 does the same thing, i think its more of a fail safe than anything else. But i have driven for way over 15 miles with my DTE showing "---"

Its kind of a game ive made fore myself, when is the z going to ACTUALLY run out of gas lol...It seems like it will run for ever even with the gas gauge needle buried way past the Empty mark...

 

I still have 7 gallons left when my DTE says ---

 

I have a 2003 and my mpg gauge is very accurate. I say this after testing against manual calculations (“the old-fashioned way” using gallons at fill and miles driven, calculated over a few fills.).

As terrasmak suggests, I reset the computer with each fill, but record the mpg value. I then add the number of fills and average the computer’s mpg values; and compare this to my manual calculation that I maintain for several fills. The values are always very close. --Spike

 

 

Artichokes are safe... do nor fear the unknown. --Spike

 

Which just makes me wonder why mine varies so much.