On my 06 coupe w/ navi, when I click on the fuel economy button to see how im doing, i notice something very strange about the instant MPG. Why is it that if im doing 60 cruising in 6th gear and just the pedal in the slightest tap, it brings me down to like 9 mpg, and when it gives me a quick average it says im getting 12.3. Im not sure if the average is really an average of all the driving I do or just when I go to that fuel screen...if its all the driving that sounds about rite cuz i like to hear my intake lol, but when i goto that fuel screen I try to drive easily on purpose just to see what kind of average it will give me and it still sucks.

 

I've never messed with the Nav on any Infiniti G35 other than my '04 Coupe....

But the way mine works is that it averages out your fuel economy over the course of the reset-cycle. By "Reset-Cycle", I mean all of the time that the motor has been started since the last time you went into your NAV systems fuel economy screen and hit the reset button.

If you drive around normally for like 3 or 4 tankfulls of gas without resetting the Nav's fuel economy thing, and then you go for a real aggressive drive for like 10 minutes straight.., you'll probably see your fuel economy printout will be something like 17 to 19 MPG(don't mind the numbers, they're just examples) and will only have dropped by like .5 to 2 MPG from what it was before your aggressive driving stint because it's been averaged out over the whole length of that reset-interval. On the other hand, if you hit the reset button, and then go drive around like that same retard for the next 10 minutes straight.... you'll probably see your fuel economy readout say something like 7 or 8 MPG.

Don't quote me on this, but it seems like the way the system works is that it logs how many miles you've driven on the current reset-interval and divides that by the amount of fuel that the system thinks the car has used over that interval to come up with the fuel economy number that you see on your screen.

I haven't seen any strange behavior that you mentioned about how it seems to measure only based on the time since when you navigated through the NAV systems menu's to get to the real-time fuel economy screen. The only thing that is real-time related to fuel on that nav screen is the little green leaf which indicates what the calculated fuel economy is in my car at that exact moment.... so that if i floor it, the real-time MPG display in the leaf goes down real low, or if i'm cruising at like 55 MPH in 6th gear it will say something like 30 MPG. On a side note, I think I remember reading somewhere that the NAV systems on the newer Infinitis don't use that stupid marijuana-looking leaf thing anymore.... which is probably good, because I find it to be a pretty idiotic way to display it.

 

I drive my car pretty hard, I too like to hear my intake and mrev2

i get 15.5, not sure why you would be so low. I think thats the lowest ive ever heard

 

"the NAV systems on the newer Infinitis don't use that stupid marijuana-looking leaf thing anymore.... which is probably good, because I find it to be a pretty idiotic way to display it."

^^LMAO!

 

lol its actually quite fitting to how to i drive...considering i also do mostly street driving i live in brooklyn. I only do highway to work which is the belt parkway and even that can sometimes be like street driving with all the traffic. -=\