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

 

[Eagle18g]

So i just got a 95 Talon tsi awd and i love it. i hav been driveing every where. the only thing is when i go to fill up on premium gas i figure out the gas mileage i got on the last tank and i get like 15mpg i have only filled up like 3 times but i was figuring talons would get somewhere in the 20's i havent tuned the boost but i have a boost gauge and im runing like 12psi right now. anyideas of what might be the deal?

 

[mjarrell20]

Are you racing through the city or are you driving like a normal person, cause I get about 25mpg. Oh is your "premium" 93 octane? Because I've been to other cities and "premium" isn't 93 "super" is. That might be something also.

 

[Eagle18g]

yeah i have kinda been driving like a maniac but i always drive like that yeah i think its 93 octane too. we have regular super then premium

 

[mjarrell20]

Control your driving a little better, yeah i know it's hard to do in these cars, and change your air filter and your mpg should go back up.

 

[X-Rated GST]

hmm....at least once a day i tend to do some "spirited" driving and i manage 22.8 mpg and that's on california's premium piss...

 

[iceman21221]

yeah this reminds me. i need to check my mpg ratings.

 

[Syndicate13]

On the stock turbo and even on my 16g I used to get around 18-20. Now on the Green I routinely average 25 and over 30 on the highway. Driving in vacuum is good for the wallet.

 

[want_a_gsx]

16-18 mpg, 50/50 hwy and city. my motor is shot. i really hate my car right now

 

[VicBoost]

My gas mileage isn't that great either i think i'm going to check out my o2 sensor and clean it out. But anyways are their any tutorials of how to get better gas mileage outt these engine. What are the best ways to get good gas mileage outta them because i only boost once in awile...

 

[denniegst]

is your bov recirculated? i noticed i got a better gas mileage when i put back on my recirclate tube onto the bov on the stock maf

 

[eclipsemustang]

maybe your engine is worn down a little maybe you should check your compression

 

[Andrew Dahms]

I have a 91 talon tsi and have recently been getting about 10mpg (dont know exact amount (250km to a tank). Air filter, spark plugs are all good. About a year ago when I got the car I was getting 21mpg and it has slowely degenerated. I am also running 20-50 oil if it makes any difference. Does anyone know why the milage could be so low? Compression is about 130 +/- 5% across the 4 cylinders with an auto using drive, economy mode and OD (ultimate gas saver mode).

 

[talonproject]

When s the last time you changed your o2 sensor?
and how s the power ?

 

[Andrew Dahms]

I got the car last year but I dont think the o2 sensor has been changed form factory. As for power, in my info you will see that I have a 12.x track time... 1/8th mile (worst time ever seen at our track)

 

[blackbyrd]

12seconds in an 1/8th mile?!?
insane..
Do you have a logger by anychance?
Have you replaced fuel filter?
PCV valve?

 

[95TalonOwner]

Boost leak test.
New O2 sensor.
New fuel filter.
Possible clogged cat.

 

[Defiant]

12seconds in an 1/8th mile?!?
insane..

Well, he had a 10-second 60-ft.

 

[95blackGsTurbo]

I would check the o2 sensor first. That is going to cause the most trouble. Change the fuel filter for maintenance reasons as well.

 

[siceclipse]

here is the link to the maintenance schedule.
if you think you are over due based on your milage, REPAIR OR REPLACE.
http://dsmtuners.com/forums/showthread.php?t=239375&highlight=schedule


my suggestions:
fuel pump
fuel filter
spark plugs
wires
o2 sensors
clean injectors
boost leaks

 

[Andrew Dahms]

Im thinking its either the fuel filter or o2 sensor. No boost leaks and fuel system was just redone. Plugs and wires are in good condition. Thanks for the quick input guys.

 

[Dark_Horse]

Do all of the above and ditch the 20w50 oil. In a cold climate, it is unwise to run 20w50 in the winter. Actually, I would never run 20w anything. Is there any reason why you are running a 50 weight oil?

Running thinner oil will result in higher MPG. That's why the newer vehicles run things like 5w20, 5w30 etc.

Not to mention that most of the damage caused to engines occurs when the oil is still cold. IMHO if you live in a cold climate, you should run 5w40 or 0w40 year round.

 

[Andrew Dahms]

I was running the 20w50 to stop a major oil leak i found in the summer before i fixed it this spring. Normally I run 10w30, never really thought of the thick oil as a cause for low milage but it makes sense.

 

[Andrew Dahms]

Not to mention that most of the damage caused to engines occurs when the oil is still cold. IMHO if you live in a cold climate, you should run 5w40 or 0w40 year round.

Though its true that the weather is quite cold here in the winter, the summer actually gets to 30-35 C (not sure what that is in F) and the 20w50 has no problems, especially on race day.

 

[VTRICCO]

so ive had my tsi for about a week now and im only seeing about 20 miles to the gallon in highway driving the car is stock with 90k miles is this good? it seems a little low to me if it is what should i look into in order to get better economy? thanks in advance for any help

 

[blkwidow]

When is the last time you had a tune-up? Pull your spark plugs and see if they are all fouled up. Have you done any maintence since you got the car?