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

 

[Batmobile]

Just recently I did a 6 bolt swap in my girls awd talon.
Now the check engine light is on, and it's getting about 140-170 to a tank of gas...ya not good.
I finally got sometime to check the light out and it came up as:
Fuel Pressure Solenoid Malfunction
Does any of yall know where this soleniod is?
It's on a 96' tsi awd.....it's bothering me that I don't know where it is. The other code it threw is the:
Evaporative Emission Control System Purge Control Valve Circuit Malfunction
this I don't know where is also.
So if I could get some help here guys/gals.
Thanks

 

[tigerstalon]

Try this thread for the Fuel Pressure Solenoid:
http://www.dsmtuners.com/forums/showthread.php?t=140564&highlight=fuel+pressure+solenoid

I can't help you with the Evap Control code, but I'm sure if you search for it you'll find some stuff, just like I searched for the Fuel Pressure Solenoid in the link I've posted.

 

[air23cary]

i will be lucky if i get 200 miles on my first tank of my new talon (91 tsi). i just had a tuneup done, boost leak test, new plugs etc. only mods are 3 inch turboback exhaust and 16g set to 14 psi. i know my mileage shouldn't be great but it shouldn't be this bad either. what is wrong with my car? is it the o2 sensor? how much will it cost to fix?

 

[SpoolnTsi]

It could be the o2 sensor but that will pull a CEL after so long. Could also be a bad fuel filter, dirty injectors, bad gas. Do you have access to a logger???

 

[air23cary]

no not really......i can take it to dogbox racing thats the only place near me

 

[Defiant]

Until you give us actual MILES per GALLON, we don't know if you're "horrible" or not. "Miles per tank", especially in the whimsical world that is the DSM level sender, is less than meaningless.

 

[xspsi4]

Yeah I am haveing the same problem with my 1g, I have a auto awd tsi with 450 injectors and 20-22 psi and I get 100 miles tot the tank, No afc though and a new o2 sensor.

 

[dsm4life]

Will bigger injectors effect your gas mileage automatically or is it really up to your right foot ?

 

[iisbernhard]

dayumm...talk about bringing a thread up from the dead .... i posted in here a year and a half ago and now someone posts

 

[oddrob]

As long as this has been bumped, a car that is out of alignment will drag and get back gas mileage as well. I picked up 2 mpg in my GVR4 with just an alignment, both rear tires were toed in.

 

[crankbender]

Yeah I am haveing the same problem with my 1g, I have a auto awd tsi with 450 injectors and 20-22 psi and I get 100 miles tot the tank, No afc though and a new o2 sensor.

Your ECU is tuned for the smaller injectors. When you increased them you started just throwing fuel away. That said you are running 20-22 psi on a 13g and no fuel control so you may very well have some other problems

Don't mess around with the fuel unless you do it right. Turn your boost down now (the fact tha tyou are getting to 22 psi and not hitting fuel cut should be a sign). Get some sort of fuel control and a 2g mas.

 

[fwdturbobov1996]

ok im getting 30 miles to the 1/4 tank.. yes i said 1/4 tank .. thats 120 a full tank ... wtf is this shit .. i just replaced an o2 and the cel is not on .. what next ? a tune up or what else could be wrong.

 

[Redmachine]

how are you driving it? What is the traffic like?I can get 120 per tank here in houston, but only if I am on the throttle all the time.If you drive her gently and thats not what is causing the rapid loss in fuel, Check your fuel lines both metal and rubber. You can usually spot a leak in the drive way right away in the morning. Next yes do the tune up. Hope you find out the problem

 

[L2RTSiAWD]

Edited the thread.

Let's try and keep profanity out of the thread titles.

 

[OneFastEclipse]

I have my WOT tuned out pretty good and it makes decent power. My question is, is it unsafe to run a little lean at low throttle just driving around town? I am using a SAFCII to tune with and I thought I would run a little lean when cruising but keep my Hi throttle fuel where it is. How do I know what is too lean? Thanks!

 

[CanadianTSi]

If you try to run lean the ECU will just compensate and add more fuel, just get your fuel trims close to 0 for the best economy

 

[fwdturbobov1996]

sorry on the langauge. I drive it like a granny .. Could I need a new fuel filter ? or just a tune up ? or could the gauge be off ..

 

[Thunderskull]

Is there any sign that you're running particularly rich? Any black smoke out the exhaust? Normally, my first thought would be o2 sensor. You could hook a voltmeter to the o2 wire and see if it's cycling properly. It might be your new o2 is dead too. A fuel filter is a possibility also. There is also the possibility that your ECU is damaged. That will also cause you to run rich and get crappy gas mileage. Find somebody with a scan tool or a logger and see what's going on with your engine. Are you having any other symptoms?

 

[fwdturbobov1996]

car idles and drives fine, no black smoke , o2 sensor is new . im going to see if my plugs are black . well this morning i unhooked my battery and i put it back on i turned the key and i heard this loud ass popping sound ... it kept doing it . i tightened the clamp down and it started up fine .. could the popping have blown something, it just sounded like it was trying to make a connection .

 

[Redmachine]

I talked to my brother who is a paid mechanic at the shop he works at. He says it is possible you could have burned a hole in a piston causing fuel to just dump in the cylinder, or you could have a fuel injector that has kicked the bucket. I say you have a major problem if you drive it granny like and still get piss poor milage. I drive granny most of the time and I squeeze out 400 miles here in houston.

 

[Defiant]

Distance per tank, especially in the haphazard DSM gas gauge, is worthless.

How many miles per gallon? Fill the tank, set the tripmeter, drive three days, refill, divide.

 

[aliczander]

i get around 300 miles to the tank when i drive like a women... but then when im driving like an animal i still get allright mileage between 250 and 275.... ps finaly home from my trip... figured it up yesterday a little over 8,000 miles of driving like an animal though 8 states and back up and down mountans and all i got is a cell for my o2 sensor, i think i have a short some where in it though coz it will ocassionaly go away then ill hit some water or what not and it will come back.... plus i was going though the moutains and the air was so thin that my car stated running like crap... pulled over checked the cell and it said it was running lean.. so i let the ecu cycle for a little bit cranked her back up and she ran like a porno star once again
i love my baby and im never gettin rid of her ever

 

[fwdturbobov1996]

it would take me like 2 weeks to use a full tank of gas..


is there anyway to check the injectors .. and wouldnt i notice something diff if i had a hole in my piston .

 

[9D9 MITSU RS]

I have a heavy foot and usually only get around 120-150 on a tank (filling up around 1/4 tank) with city driving. With some highway miles in there, I usually get about 250+.

You're probably just going to have to REALLY baby it if you hate filling up.

 

[bkblazen2003]

damn you guys have some amazingly low mileage numbers. i get like 24 to each gallon with mods on my car. maybe because new york city is closest to sea level. cars high above sea level work harder to make power.