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

 

[FrostbyteTalon]

Ok, I have a '95 Talon TSi AWD with '85k miles. I'm running 14psi and the only mods are Filter and adapter, Dejon tool intake, and 3" Catback exhaust. I've been getting 17mpg city and about 26 mpg high way. I don't understand the HUGE difference. City driving which is most of my driving I get maybe 240 miles per tank. High way I got around 310. I logged the car and my o2 sensors were both .96-.98. Can anyone help? Oh yeah, and I had it compression tested... between 176 and 180 across the board. Can anyone help? its getting annoying.

Oh yeah, and Plugs and wires were just replaced... this help a bit, but not much.

 

[xcelr8n]

thats not bad gas mileage man.
city driving kills my car to, i doubt you have anything to worry about

 

[FrostbyteTalon]

then why do I have a friend with a 97 gsx that runs high 12s in the 1/4 that gets over 300 miles per tank city driving? He's got a mods list longer than the dictionary.

 

[xcelr8n]

maybe becuase he tunes his car for it?
im sure with that many mods hes doing it as he wants.
runs lower boost? and runs leaner?
bigger turbos spool later in the rev band, and maybe he doesnt boost at all in the city because of it

 

[4geze63]

your mileage is completly normal, try changing your fuel filter, spark plugs and anything else related to fuel improving the fuel efficiency

 

[1sick91tsi]

ok i have a 91 tsi all wheel drive talon, and to me it seems like im gettin real bad gas mileage,like only 150 to the tank, thats babying it and only runnin 13 psi, this is what i have done then tell me what u think could be wrong,16g turbo, dump pipe, 2 1/2 inch down pipe, 2 1/2 stright throug exhaust with high flow cat, upper intercooler pipes, 2g throttle body elbow, magnecore 8.5mm plug wires, dejon tol intake pipe w/k&n and removed honey combs, hallman boost controler running 13 psi, ported exhaust mainfold and turbo inlet, cant remember anything else. any advise would be grealy appriated, i was thinkin maybe o2 sensor? thanks for the help

 

[95GSXBLUR]

is yoru check engine light on? because it's probably your front O2 senor. do you have a fuel leak someplace? check your filter and connections.. i only get about 200 to the tankwhen i drive around regardless if i push it or baby it. so check those out and lemme know what's up.

 

[1sick91tsi]

nah no fuel leak or anything, but i did just clean my k&n, got new plugs, changed fuel filter and now it looks like im getting like 200 to a tank. im at 150 miles and i have a quater tank left so if 200 is normal i guess im good to go. thanks for the help, and one more thing me check engine light wasent on but do u think i would benefit from puttin a new o2 sensor in anyway, thanks agian.

 

[95GSXBLUR]

well i say if it works don't fix it. i'd wait until they go bad. you'll get a check engine light if one does go bad.. i push my car hard all the time probably why i only get 200. maybe someone else has some light to shed.

no prob dude

 

[Devistator]

95 GSX, Evo 16g, walbro 255 HP, at about 15 psi, 3" intake, manual boost control, stock 450cc injectors.

My MPG is 13 (city and highway combined)
I tried to cut fuel from 10-15% in 2k-5k range and nothing (DSMLink).

Still running rich.

Anny idea Tuners???

 

[Blk_99gst]

Front o2 sensor working? ie. voltage toggling back and forth from .2 to .8 volts.

 

[Devistator]

got new one and tog. between 0-0.98

 

[Mackzero]

Do you have an adj. FPR? with that size of pump you really should get one if you do not have one allready...

 

[CanadianTSi]

Do you have an adj. FPR? with that size of pump you really should get one if you do not have one allready...

Agree'd

 

[Devistator]

don't have FPR. Tried to adjust fuel by DSMLink bat that's just when WOT is applied.
Anny idea of good and cheap FPR?

 

[UndergroundR32]

I would "think" that a fuel pressure regulator is a fairly simple (daring word to use) device, and there aren't any that I would stay away from. The SX/Aeromotive FPR's are very popular and work well. I'm happy with mine.

 

[blitz43]

heys guys is it true that 2g turbo gas economy sucks as you modify it?? or does it improve it???



i just got my uicp all of it and turboxs h-34 valve also a k&n fipk kit and i think my gas milelage dropped a lot!!!!

anyone know what to do???

 

[Defiant]

The bigger the fire, the more logs you're going to need.

 

[blitz43]

The bigger the fire, the more logs you're going to need.

..... thats sounds aboutr right

 

[ozzeran]

true. but sometimes when you take the bottlenecks out of the system and drive it normal you should gain a mpg or 2, but usually you're too busy having fun with it and there goes the mpg. I'm really liking the factory gas mileage on my gst and may just leave it stock and buy a project car.

 

[Coup D E'Tat]

With the mods in my profile, I get between 20-22 MPG. This includes going WOT on occasion, and driving like a grandma the rest of the time (I try not to boost under acceleration.)

 

[speedracer91]

i have a 91 Talon TSi awd w/ an a/t it seem to use a lot of gas..like so bad that my dads lincoln ls V8 gets better mileage is something wrong is there a secret to better mileage?

 

[al5dsm]

One of your O2 sensors is probably bad

 

[speedracer91]

how much is it to fix....is there a way around it?

 

[Aikouka]

What is your mpg? You know that the AT DSMs are rated at a lower MPG than the manuals. Right now, I get 26mpg with my manual AWD. If your car hasn't been tuned up, give it a tune-up. If that doesn't help, then start checking sensors like the O2 Sensor. Does your car idle correctly?