[QUOTE=dreamweaver]I do a mix of driving in my 05 coupe speed..i have 2800 miles on it now. factory computer tells me im getting 20.9 miles to the gallon.. im not complaining im happy... very happy. i run premium gas and i dont drive like an old lady either...[/QUOT

wow! that tells me that it has t be something besides a dirty filter, a clean filter will never give me 10 more miles per gallon or 8 or 7...

 

I have a z tube and a still air box thats my only mods now.... and it picked up 1 mpg since i instaled it so again im very happy

 

yea an extra 1 or 2 mpg is great wen u are already getin 15+ but going from 10 mpg to 11 or 12 isnt much, im jus worried theres a bigger problem guys...any thoughts?

 

check your plugs? for starters gas is getting wasted some where? perhaps your washing a cylinder down and that would not be good... check tire pressures. you def have a problem if your only getting 10mpg. start with the basics. look at filters and then probe deeper

 

whoooooops miss read SORRRRY i thought you only had 14 miles LOL SORRY

 

...

 

I'm getting like 20mpg too! I would take it back to a dealer to check it out.

 

1. get a oil change
2. get a new air filter (k&n) from www.everythingg35.com or any website
3. get a ztube


im sure after an oil change and new air filter you should be fine.

 

How do you calculate mileage. Not trying to sound demeaning, just want to make sure. (I'll admit, I've gotten lazy now that I have the navi display ) Give us your procedure and numbers.

Curt

 

syntethic oil change done 1000 miles ago, but im defently gonna get a new filter, a lot of you guys have mentioned it, thanks everybody! very helpful

 

after u fill up reset ur TRIP A/B then next time you fill up see how much you filled up for example 16.4 gallons then divide how much is on your trip by 16.4 and you'll get your average MPG.

so say i got 240miles on the reset odometer trip A and i fill up next time at 16.4 gallons then i do 240/16.4 = 14.6MPG (average)

 

whenever the gas ligh goes off, i ussually wait about another 30 miles since ive read that it usually goes off with about 4 gallons left and i must say its tru, so ussually fill up 18-19 gallons n then jus do the math..i get anywhere from 180-210 since ive gotten the car n this is again on CITY DRIVING so yea im averaging 10mpg no matter how i drive the car

 

maybe u are in denial u really have a Hummer H2 & u just think u have a G35

I dont drive my G enough to klnow my gas mileage but I get 12-13 in my Escalade ESV ...so @ 10mpg in a G u need to service that baby big time!!

 

get a supercharger or a twin turbo that would solve ur problem...

 

Strange. I get 21 mph average with my 05 G35 Sedan 6mt. I use Shell and Chevron gas. I also drive 60% city and 40% highway. 23k miles here.