Adam2001WS6

iTrader: (1)

Even when I'm PURPOSELY not flooring it and coming out of lights like a grandma, I get terrible gas mileage. Even after a a full tune-up, I thought i would get much better gas mileage. I've only had one tank full of gas since the tune-up, but it's pretty much the worse total mileage already. I'm talking like 150 miles and I'm past the half way point on the gauge... What am I doing wrong or what can I do to help this? Thoughts, insights?

98cherrySS

iTrader: (2)

I only wish I could get 150 miles out of a half tank! Realistically I'm getting between 180 and 200 a tank. I think your doing all right. What did you get before?

Adam2001WS6

iTrader: (1)

No, I'm well PAST the half tank point with only 150. I'd say half way between 1/2 and 1/4 left. Most I've gotten out of a full tank is about 250. Normally I get 215-235. But I see threads on here where people are talking about getting 23-24 mpg?!?! That's like over 300 miles.... I'm like, what's the deal here.

chavez885

iTrader: (12)

Full tune-up, what did that involve? Also, 6 speed or auto? What gears, what tires? What kind of car? Car tuned, mods?

P.S. any o2 sensor codes?

2KThunder

iTrader: (4)

I get like 13mpg hybrid city/highway and 23 straight highway

TireSm0ke

iTrader: (1)

Man im lucky to get 100 miles to the halfway mark. I dont get it either.... change your plugs/wires, air filter, fuel filter, clean your throttle body, and if none of that helps try new o2 sensors and a tune

wht01ws6ta

iTrader: (45)

That doesn't seem bad when you're talking about city driving. I doubt I get near that but then again I like to mash the loud pedal a lot. I mean gas only costs half what it did a few months ago right...

twitchtwice

iTrader: (12)

i get 200-240 with 10 gallons (i always fill up when im around a 1/4 tank) but i dont drive like a maniac.

Adam2001WS6

iTrader: (1)

Full Tune-up == Plugs, Wires, Air filter, Fuel filter, Oil and filter changed

Car is totally stock... gears (3.42 for WS6?), no tune or anything changed from factory settings.

Falken tires on stock WS6 17" wheels

The SES light went on a few months ago and it through a TPS and O2 sensor code. Changed the TPS first and the light went off. I just figured the O2 code was "old". Maybe I should check the O2 sensors?

wht01ws6ta

iTrader: (45)

3.42 if it's an M6

Black FormulaLs1

iTrader: (10)

how many miles? maby it should be seafoamed? and fuel filter's changed out then see whats what....

9000th01ss

iTrader: (10)

First of all you need to check it the right way. Fill it up and reset the trip odometer. Next time you get fuel fill it up and write the mileage down. Divide mileage by gallons for MPG. Do this a few times to get an average.

My A4 Z28 has been getting around 240 to 270 miles between fill ups. Last was 263 miles so it got 17 MPG, and thats no highway at all. All the "whats your gas mileage" threads are probably absolute best seen.
If I posted my best it would be my M6 SS on a highway trip, it got 27 mpg. Non highway it gets around 14 to 18 mpg.

transam77

dito if you wanted good gas milage your deffently in the wrong type of car... Some things that might be hurting it worse though are somethings you may have done to it. For example do you have gears upgraded? I think stock gears are 2.73's but if your running 3.73's or 4.10's its going to make it worse and those people talking about 24 mpg could be driving 6 speeds and know how to use them if your in an auto thats bad. no ofense though ls1's shouldnt be the car of someone who is worried about gas

wht01ws6ta

iTrader: (45)

LS1s are actually pretty good on gas, not great but very good considering how much power you can have and still have very decent mileage. I've gotten 27 highway going WOT at least a few times and running the AC and there's more than a few that claim 30+ but do a search and you will see that.

Gear ratios: GU2 = 2.73, GU5 = 3.23 and GU6 = 3.42

http://wiki.ls1tech.com/forums/showthread.php?t=412366

Adam2001WS6

iTrader: (1)

Yeah, it's an M6 with 3.42 and as I mentioned earlier, the fuel filter WAS changed.

Car has 110,xxx miles on it and I seafoamed it completely right before the tune-up. I know it's not going to get great gas mileage given the V8 plus quite a bit of stock hp right out of the factory, I just thought there could be something that is keeping mpg low.

I figure when I get the intake/exhaust sides modded, perhaps a tune or 2 will get things running a little bit more soundly...

chavez885

iTrader: (12)

Interesting, like someone else said, make sure you are calculating your MPG correctly. You might try clearing your MAF (there is a cleaner for this), a dirty MAF could cause some odd reading and eat up some fuel. Also check your tire pressure and make sure they are all good. Also for city driving, I don't see you getting over 20, so don't confuse that for when folks say they get 20+

I get probably 18ish in the city and have to fill up at about 235ish miles. But for all highway i can usually go to about 330 or so depending on how fast i was going.

Adam2001WS6

iTrader: (1)

Isn't it just as accurate to reset the Tripometer (which I do everytime I fill up) and take the total number of miles divided by the 15.5, the number of gallons the tanks holds? As I mentioned in an earlier post, I normally seem between 220 and 235/245 (250 at the most I ever got on a full tank), so according to my calculations that...

220/15.5 = 14.19 mpg
235/15.5 = 15.16 mpg
245/15.5 = 15.81 mpg
250/15.5 = 16.13 mpg

Seems pretty low to me, especially babying the throttle and not mashing the accelerator pedal everytime I come out of a stop light. I just wanted to know everyone else's averages to see if I was leaving something on the table. This tank, the one immediately AFTER the full tune-up, which one would believe I would get the BEST mpg out of the tank, is actually looking like it'll be the worst.

Adam2001WS6

iTrader: (1)

Oh, and the fuel filter IS NOT leaking. I've checked several times at idle and after a drive.

99345hp

No, because unless you are actually putting 15.5 gallons in it, then you are calculating more gallons than used. I dont think you can actually use 15.5 gallons, if you do, then you would be rolling into the station on fumes.

To the OP i have only checked my MPG while on highway trips, so I cant tell you if what is wrong if anything. I average 220-240 miles on the first half of a tank on the highway. I usually average around 26-27mpg highway. I would guess around 20 in town, but I havn't ever checked it.

chavez885

iTrader: (12)

No...look at how many gallons you're putting in, divide it by that number...