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

 

[Davidle]

sounds good. thanks buddy, have fun playing raquetball.

 

[Golden4g63child]

could u tell me what kind of spark plugs, spark plug wires, and oil filter you use. NGK's??? Thanks.

Im currently using the following:
- NGK copper spark plugs (BPR7ES)
- Magnecore 8mm spark plug wires
- OEM oil filter from the dealership (the big fat one)
** I think you meant what kind of fuel filter right?!*
- OEM fuel filter from the dealership
Just letting you know that if you don't have any bpu (basic performance upgrades) yet, than you should use a different spark plug (NGK BPR6ES I believe) since the ones I have are a little bit colder that the other ones.
Hope that helps you.

 

[Davidle]

yeah, sorry, i meant fuel filter. Dont know what i was thinking. Thanks for the info. I will probably try those later, and hopefully it helps. Where can i get the manecore wires for a good price? is there a website i can get it at?

 

[Grinder5]

sell your turbo and get an n/t. Economy and performance do not go well together. I probably average about 29 mpg on every tank. If I drive straight highway I can score about 32-33 maybe, haven't figured it too well. Turbos eat gas cuz it takes more fuel to keep the a/f mix right. If there's one thing to be said for n/t, it's that they get good fuel economy. Though for the amount of power that you get from a modded turbo, they get pretty decent economy too. I'd love to see an old muscle car make 300hp and still get above 20 mpg. MOst don't get 20mpg stock, so i'd be happy with what ya get. Could be worse.

 

[Raph]

i get about 500 to 600 kilometers on a full tank,thats about 350 miles on a full tank,nd every time i fill up i switch between 95 and 98 octane.i kinda figured that that helps.

 

[Davidle]

over where i'm at, the gas stations has octane of 92, nothing above that. What brand of Octane Booster do u think is best????

 

[13secGST]

Horray! I just got 248 miles to 12.2 gallons...thats just over 20mpg...and I don't even have fuel or turbo upgrades...that guy getting 350mpt damn thats good...even when I get new plugs and wires...I don't think it will help me THAT much...ps what do you have your tire pressure at...I'm going to bump mine up to around 40 cause the max in my tires is 44 I think

 

[13secGST]

I heard octane booster was bad

 

[dsmstunna]

I just got my car, and only on my school permit but I have 2 gas stations near by and the best i can do is 90 octane between the 2 of them. Should i be running this? It's mostly stock right now. I can see what other stations near by have even thoe I'm not susposed to drive out of the way to get fuel. but i don't think i will get any better than 93 It sucks here in Iowa

 

[13secGST]

I only get to use 91...I think thats the highest they have in Cali

 

[Raph]

here in germany we can get up to 99 octane(Shell optimax) other than that i usuallz fill up with 95 or ccasionally 98 octane and get 500 to 600 kilometers on a full tank.

 

[Raph]

and always check your tirepressure and keep your ride in a good state of tune,air filter and plugs, and the quality of gas does count, maybe spending a little more on higher octane will turn out for better mileage and u save money that way.

p.s: i filled up once in france with 91 octane because it was a sunday and i was in thje french country side where every thing looks the same
and everyone speaks french except me and i managed getting about 400kilometers out of the tank.

 

[Gangreen]

I just bought my 90 talon awd turbo 3 months ago and I have been getting bad gas mileage ever since. I figured that it was probably my O2 sensor so I got a new one a month ago and it helped out slighly. I have been letting my car warm up for 15 min. before driving it because of the cold weather and when I start drivng, you can actually watch the gas gauge go down. Could it be leaky injectors? Please respond with any ideas.

-thanks Jon

 

[Tut4u2]

change ur air filter, that always helps

 

[Raven457]

Originally posted by Gangreen
I just bought my 90 talon awd turbo 3 months ago and I have been getting bad gas mileage ever since. I figured that it was probably my O2 sensor so I got a new one a month ago and it helped out slighly. I have been letting my car warm up for 15 min. before driving it because of the cold weather and when I start drivng, you can actually watch the gas gauge go down. Could it be leaky injectors? Please respond with any ideas.

-thanks Jon

It could be... do you see or smell gas around the top of the engine?

 

[cucumber]

You can't drive around with the pedal mashed to the floor all the time.

 

[Misundaztood]

What octane do you use? I'm assuming the highest grade since your turbo, but that could be your problem...

 

[rubbersidedown]

well what exactly to consider "bad" gas mileage? About how many miles are you getting from a full tank?

 

[Gangreen]

I have a K&N air filter with the air can and the bottom maf hacked. I use 93 usually 94 octane all of the time. I hardly ever mash on the gas and my way to school is mostly driving on a highway with takes 90 mins round trip and I use around a half a tank of gas. So iam guessing that my gas mileage is around 16 mpg (it used to be 12-13 before i put a new O2 sensor in).
My mods are:
-turboxs mbc with my boost set at 15
-k&n cone filter
-ported manifold,O2 housing,turbo,and wastegate
-hacked aircan and lower honeycomb on maf
-full catless exaust

Much Appreciated
Jon

 

[cucumber]

Originally posted by Gangreen
I have a K&N air filter with the air can and the bottom maf hacked. I use 93 usually 94 octane all of the time. I hardly ever mash on the gas and my way to school is mostly driving on a highway with takes 90 mins round trip and I use around a half a tank of gas. So iam guessing that my gas mileage is around 16 mpg (it used to be 12-13 before i put a new O2 sensor in).
My mods are:
-turboxs mbc with my boost set at 15
-k&n cone filter
-ported manifold,O2 housing,turbo,and wastegate
-hacked aircan and lower honeycomb on maf
-full catless exaust

Much Appreciated
Jon

Yeah your MPG is still a little low, 16 mpg on the highway?

 

[Gangreen]

I have talked to people around my area (PA and the temp. has been in the single digits.) and they have been having pretty bad gas mileage. They say its probably because of the additives that are put into the gas so it doesnt freeze. I have only owned my car for a couple of months and its been winter since i've had it. Do they really put that much #### in to the gas to mess with ur mpg that much?

 

[rubbersidedown]

i'm probably just reaching here but maybe its because you hacked your maf? try and put the honeycomb back in at least. just a thought. worth a try isn't it?

 

[InferiorWang]

won't hacking the maf cause uncounted air and a lean mixture? at least, that's the way i thought it worked.

 

[rubbersidedown]

hence my saying "maybe i'm just reaching here"....

 

[InferiorWang]

i wasnt ripping you or anything, just putting out there they way i learned it.