After putting 15.401 gallons in, your tank would have been "full".

You then drove 224 miles which then required 14.904 gallons to get you back to "full". Means your MPG was 15.03 for the period. Either something is up with your car or you drive it like you stole it all the time.

I suggest you sign up for www.fuelly.com. You just punch in a few numbers off of your gas receipt everytime you fillup and it computes the rest.

 

Um, it is very relative. You filled up and zeroed the trip meter. Then after driving 224 miles you filled up again, and it took 14.904 gallons.

224 ÷ 14.904 = 15.03 miles per gallon.


I think I got as low as 13 mpg while flogging my car at the Tail of the Dragon in the mountains. It's hard to say if you're driving the car hard, or just have a short city driving commute.

If you just got the car, it might be due for a tune up, replacing all fluids like oil, trans & diff would be a good start.

 

Im getting on average about 250 miles to the tank in the city and the highway in my 6mt. I cant help it, I have a lead foot.

 

I have gotten 27 mpg on the highway, which would equal out to a little over 500 miles per tank. Something is wrong with your car if you only get 150 miles per fill up. Looking forward to you getting back to us with your update. In the meantime, do a few things such as check your tire PSI (you may have done that). Good luck.

 

[QUOTE=viciouzgamer;6557891]So as you all can tell im pritty new here, I just bought a G 35 Coupe AT and i was wondering if around 120-150 miles highway per fill up is normal.
I traded in a BMW 323i e46 5MT
my 99 323 5MT got 33mpg on turnpike cruising 70mph.
my 03 G35 6mt gets 27.2 " "
I believe much of this success is due to the extra 2 degrees extra timing I had dialed in by my neighbor with his laptop and program.
on typical turnpike cruise there is very light load and the 2 degrees comes into play and afford better mileage in my opinion...the extra timing also provided more low end torque with judicious use of gas pedal. naturally with full throttle the computer will pull out all necessary timing to keep from pinging
keep in mind that tire pressure is important and I use 36psi.

 

I drive a little crazy at times, but i get about 19.2 MPG according to the gps info. I think if i shift at like 2.4k instead of 2.8 would increase it a little.