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

 

[ToxicAvenger]

i bought my car second hand and i was going over the service reports from the old owner. i ran across one that was talking about how his mileage had dropped from around 23 mpg to 17. the shop couldnt figure any reason for it, and suggested that he change the spark plugs and wires, which he did. but i still only get around 17 mpg and i was wondering what i could do to improve the mileage. btw my car is stock right now.

 

[GSX90]

Try replacing the o2 sensor...or test to see if you o2 is working properly...

 

[ToxicAvenger]

how do you test to see if it is working properly

 

[ravage_talon]

This may be a very simple fix, check the air filter, if you hold it up to light and cant see light through it, change it.

I put a K&N filter on mine about 6 months ago and my mileage went up another 4 to 5 mpg. and there is a noticable increase in power too, hehehe.

 

[CaliDSM]

i only get 240 on average from a tank of gas and i put in 14 gallons. i use 91 octane from cheveron.does anybody get alot more?or could i have some problem with my car

 

[boostineklipz]

change air filter, spark plugs and wires if they havent been changed in a while

 

[snooze]

I get about 215-230 on 13.5 gallons, so that sounds right to me. It depends on what type of driving you do, city/highway, 240 sounds right for city driving.

 

[bubbaGSX]

those mileage is hella good compare to mine. i get around 170-180. if im lucky ill hit the 200 range.

 

[out there]

ditto here, i get about 180 on 12 gallons of 92 octane... then again, mine is awd. my subaru forester gets 210-240 per 12 gallons, and that's about 80% in town with a few short runs on the highway. and, it's an auto.

 

[talonted_one]

bad gas milage may mean a dying o2 sensor

 

[Grinder5]

Turbo cars get bad gas mileage anyway. How long have you had the car and has it gotten that gas mileage since you bought it?

 

[RedTurboEclipse]

hmm. i have a 2g gst.. and i get 250 if i drive conservative.. well not really.. i can throw in mix driving with hard and normal driving.. but this is vented to the atmosphere bov.. i should be getting more than 250 per tank..

 

[cucumber]

I recommend keeping the foot out of WOT.

 

[ASZRAEL1266]

My car is a 12 gallon tank if i do nothing but hwy miles with alittle city i can get my gas to strech out to 250 miles to a tank of gas. but normaly in city driving i will get about 200 miles to a tank of gas. Ive been told that we have a 14 gallon tank or somthing like that. but i drove my car till it was on the E and the fuel light was on and woudln't go off and i toped off my tank and it only took 11.6 gallons.

 

[Tevenor]

Hmmm. I get 22 mpg and i WOT almost everywhere I go on 93. That is in both the 96 and 92.

 

[SpyderGuy]

My car was getting bad gas milage. I poured in some Valvoline Synpower Fuel Injector Cleaner and that seemed to help out a bit.

-SG

 

[Laser-man]

i get like 400 miles to a tank and 1/4 (i ran the tank down all the way, put 5$ in it and it gave me 1/4 tank after that was gone i had went 400 mile) and i drive the piss out of my 1.8 WOT all the time no time to slow down i would be going to slow

 

[out there]

Originally posted by ASZRAEL1266
Ive been told that we have a 14 gallon tank or somthing like that. but i drove my car till it was on the E and the fuel light was on and woudln't go off and i toped off my tank and it only took 11.6 gallons.

do you have the manual? my manual says 16 gal, and i've driven it down into the e, when i filled it, i only put 12.5 gal in. maybe it's some sort of reserve thingy? y'know, for when you start panicing(sp?) to find gas as you hit the e, just another 4 gal to get you where you need to go, ya gotta love those great dsm engineers

You must be logged in to view this image or video.

 

[GreddySpyder]

What kind of gas mileage do you average... also what kind of dsm do you drive and what psi are you boosting and do you have stock or aftermarket injectors if you are turbo. I have the stock turbo and injectors and have been boosting 15psi until just today when i put on a mbc.

 

[98TsiAWD]

20-22 mpg city, 28+highway.

Here are my mods:

K&N FIPK
1g BOV
Brode Upper IC Pipe
MBC@15psi
Hacked Dump Tube
Sheetmetal Cold Air Box
Greddy Lower IC Pipe
Rewired Fuel Pump
Accel 8mm Blue Plug Wires
NGK BPR7ES Plugs
Dejontool 2.5" Turbo Inlet Pipe

 

[herostar]

i'm mostly stock, but i get about 26mpg average, unless i rod it

mods:
intake
catback
dejon tool uip
1g bov
18" rollers

 

[Zuggie]

i get crappy gas mileage, about 270miles on a tank. I used some X1R fuel system treatment which help gave me about 50 more mile on my Sunfire, but hasnt helped me at all on my eclipse. if you know a way i could improve it let me know

 

[Enigma_Man]

I drive a lot of highway.

~24 mpg, 16g, 15 psi, rewired pump, stock everything else.

-Jesse

 

[Airpoppoff]

how big our the 2g tanks?

 

[RACER-X]

17 to 18 in the city and 22 on the high way ..... because of my heavy foot. usually 220 to 240 miles per tank