I get about 360 miles per tank and average about 16 gallons per fillup, so about 22mpg. I drive a mix of highway and city.

arent our tanks 18gallons?

ok thats what ill next time (btw i always reset the odo at fillup)

What does your computer say? Have you checked it?

I get 120 miles every 1/4 tank on highway, with A/C on. That gives me 480 miles full tank. If we have a 20 gallon tank, then I am getting 24 mpg on highway. Can't tell you city mpg because I hardly drive it in cities.

i live in ny right by manhattan and right now i get around 220 out of a 20gallon tank, that makes it 11 for my car, which is horrendous, 93 is 2.85 around me so im losing mods to driving the car, im thinking about taking the bus for a month so i can save up for rims. stupid ny, stupid gas. oh ye, and my auto before this got 15 so i think there might be something wrong with my ecu or something cause i try to drive super slow

i get about 17 in the city and 25-26 on the highway.

but my average is around 19 since i do mostly city driving back and forth from work.

I use 93 octane.... which went up to $2.75 a gal today...

Somethings got to give @ $2.95 a gal. (93 octane) doing mostly city driving in Chicago I get about 220 - 230 per tank.

Maybe some things to check:
- under-inflated tires (even with the tire pressure monitor, they could be low).
- brake caliper maybe siezed or rubbing. Parking brake would have this effect too.
- are you driving with A/C always on or perhaps your windows are open? - wind resistance can add up to a significant loss in mileage.
- something you'd probably already have noticed but I'll mention anyway: bad wheel alignment.
- something more serious maybe your dealer should check.
Hope this helps.

Dalf, according to point number 3 if you drive with your a/c on you are screwed if you roll your windows down your screwed. I guess you have to wait till fall

actually yes my ac is on quite alot

if you drive short trips. you mileage is ok. i get same when i drive 9 miles trips.
you will get average 18-20 if you extend your trips.

With my Vortech Installed I get about 12-13 mpg City and 14 on the Highway. which is pretty sad because gas around my area is $2.99 for 91 and since I drive alot I fill up at least everyother day!! So I don't like it I remember 2 years ago when people thought paying $1.50 for gas was Alot. where the hell are those days now.

just got my black 05 g35 coupe... if i drive like a maniac on the manu-matic (sorry i know i suck for getting a non-manual..) then i can be as low as 10mpg if i reset the fuel economy thing.. but if i drive half and half automatic and easy and manu-matic and hard i'm still at around 15-16 highway and city combined...

could the fact that it's a new car effect it? because thats what they told me on my old car.. engine needs to settle in and burn things up, get clogged up elsewhere and etc...

You shouldn't be figuring it out of 20 gallons. You should divide by whatever you put into the car, and there is no way that is 20 gallons, unless you are trying to damage your car and running it almost dry each time.

There's your problem...

I get a little less than 250 mi per fill up.... but anyone who has seen me drive knows why