Bad Gas Mileage [Merged 9-6]

[99GST]

I am still getting some pretty bad gas mileage.

I am only getting about 19.7 mpg with mostly city driving shifting at 4k.
I have already replaced my front O2 sensor and am looking to replace the fuel filter.

I have a 99gst with about 55k miles on it. Should my fuel filter already be bad?

What else should I check or change? I have NKG plugs and Accel wires are on the way.

Thanks,
Nathan

 

[ADrewzki]

According to my gas gauge, I'm getting 100 miles every half tank. However, when I fill up, it usually only takes about 4 gallons. I'd say fill it back up and see how many gallons you've used. It might just be your gas gauge off. The better question might be how many miles per gallon do you get?

 

[mattspyder]

how many gallons fill up the tank about 13 right??

 

[ADrewzki]

how many gallons fill up the tank about 13 right??

16 gallons I believe. Someone correct me if I'm grossly wrong.

 

[krazywhitboy]

15 gallon gas tank.....

oh and i get 160 to a full tank...about 10-11 mpg.....my v8 mustang got better mileage....

try what everyone says, replace basic stuff
air filter
plugs
wires
o2 sensor
i tried injector cleaner (didn't help)
tried staying out of boost (as much as possible) didn't help...

i've pretty much given up all hope on getting decent mpg..... :thumbdown

 

[phalanx]

yeah I get the same exact thing, 100miles for 1/2 a tank. But when it hits empty it only takes 10-11 gallons. And it only takes 180 miles for me to hit empty. So that would mean I'm getting 16 - 18mpg, not bad considering I drive hard. I'm sure I could easly get 22-25 mpg if I drove like grandma.

 

[Defiant]

I'm not letting another miles-per-tank thread live.

MILES PER GALLON is the ONLY significant figure.

 

[Eclipse223]

Hey guys I need some help I am only getting around 220 mil on each tank on my 97 GSX eclipse and that's not running it that hard all I have is intake on it um why is it doing this help plz. it has a 123K on it and I still think it needs a tune up but I am not sure that would have anything to do with it. Thanks Guys


Brien

 

[a_scobel]

http://dsmtuners.net/forums/showthread.php?t=124669

 

[dave99gst]

i wish igot that much on my awd.
i get like 180-90 a tank (totaly stock car)

 

[olmytsi]

replace your o2 sensors and if u have a fuel pump get an afc to lean it out to where the car is "happy"

 

[Twinturbo2800]

ive been getting about 200-210 which is around 17-19 mpg i belive, not too shabby considering my RX-8 was getting 13mpg

 

[Defiant]

There are many mileage threads still open. This won't be one of them.

MILES PER TANK IS MEANINGLESS.
ONLY MILES PER GALLON HAS ANY WORTH.

 

[Fred9981]

I have a 95 gsx auto mods greddy intercoor pipes, greddy bov, injen intake, njk wires and plugs, crank pulley, 2.5 exhust, and no cat. and my gas mileage is about 15 mpg. is that what i should be getting or is that bad. is there any thing i can do to get better gas mileage. whats normal gas mileage.

thanks

fred

 

[GSXanimal]

You should be getting at least low 20s on the highway,check the o2 sensor and coolant temp. sensor especially if your car is blowing any black smoke(running rich) good luck.

 

[Fred9981]

both sensor are new

 

[Fred9981]

i get 15 mpg 95 gsx !!!!WHAT CAN I DO???? what and how do i need to check or replace

THANKS

 

[Mirage2LTurbo]

Make a throttle stop so you can only go to 20%.

 

[kahl23]

Maybe try disconnecting the wastegate arm, if your turbo is internally gated, when cruising, then when you get to the track/want to boost you can just reconnect the arm. That keeps your turbo from fully spooling, but will probably also make your car loud/buzzy when driving.





*EDIT* I'm assuming that your car is in good working order ie. no fouled plugs etc.

 

[Fred9981]

thats not the problem i have been driving like a old lady and not floored it to check the gas mileage for the past 3 fill ups and im getting 15 miles per gallon


boost is at 11 psi

i have no cat, 2.5 exhust, intercooler pipes, greddy bov, and a intake

 

[DSMnewbi]

Turn down the boost, lean it out, and make sure your o2 sensors are OK.

 

[Fred9981]

how do i check the o2 i have a a/f gauge and it seems to work

i dont have a boost controller the boost has always been at 11psi stock

 

[Fred9981]

how do i check the o2 i have a a/f gauge and it seems to work

i dont have a boost controller the boost has always been at 11psi stock

 

[ClipseT96]

Shit i get 9mpg on a good day.

 

[Tomeek]

k&n airfilter, will give you better milage, and also 9 mpg !!!!!!!!!!!!!!!!! how can that happen???? you must be running PIGrich... yeah go dyno it and/or check your wideband numbers !

 

[eclipse90gsxt]

Shift early, be gentle on the throttle, try and stay out of boost as much as possible. Make sure you have good vaccum/boost leaks. Make sure to do regular maintence to the car. I forgot the exact steps to check for a bad 02 sesnor, but if one is bad if should throw a check engine light(cel). CHecking the 02 sensor involes using a multimeter set to ohms. You can pick up a haynes manuel at a autozone/napa/advanced auto for around 10-15 bucks and it will tell you a lot.