ChristinaZ

hey guys just wondering what other people are getting for gas mileage for their stock ls1.
mine is barely getting 200 miles to a tank with premium. any suggestions to help improve gas mileage would be hugely appreciated
Thanks!

senicalj4579

iTrader: (41)

Yea would assume your car has issues. My built car in sig gets 200-230 per tank.

Undertow74

iTrader: (45)

who knows could be any number of things. Very vague description. 02 sensors, clogged air/fuel filter, fuel pump.....you name it any drive ability issues?...car been tuned?

omc8

iTrader: (7)

Well first of all welcome to the board ChristinaZ. What year is your car ? 98 had a steel tank 15.5 gal , 99+ 16.8 A well tuned car should be able under good conditions of 280 to 300 per tank. That would be an avg mpg of 17 mpg. Do you have a SES light on the dash. Have it scanned and find out want codes you have and get back to us.

Furious1

iTrader: (1)

I recommend resetting your mileage counter on your OD, fill your tank, then drive till you are almost "empty." Then, refuel and divide the mileage on the counter by the number of gallons filled. I am usually right around 20.5 miles per gallon on average. As for trying to improve mileage, as mentioned above, its hard telling where your problem lies. I would do some simple, routine maintenance, and see if you notice any improvement. Also, you might want to change your driving habits/style a bit and see if you see any difference. These cars suck down the fuel when under a lot of load...if you are taking it easy 90% of the time, you should see good mileage. If none of that works, you could have something a little more involved going on. You may need to look at O2's, fuel filter, spark plugs, MAF, etc.

redtan

iTrader: (5)

You have to first tell us what sort of driving you do and where. If it's anything like a big congested city where all you do is go from stop light to stop light without going too much above 30mph I'm not surprised. Even a stock LS1 only gets like 15-16mpg in the city if that, so 13-14 gallons per fillup (as I doubt you drain every last drop of fuel before filling up) that sounds about right.

Now if you're driving mostly highway and very easy then yeah you have some problems. Do the basic maintenance like furious1 mentioned and go from there.

14k

How do you test the MAF? Unplug it while it's running then what should happen? Does the car have to be fully warmed up to test?

thunderstruck507

iTrader: (18)

Calculate MPG first and see where you are. Miles per tank is a useless figure, especially considering the inaccuracy of the GM fuel gauge.

ChristinaZ

I have a 98 camaro. I drive to school so its mostly on the highway. It has not been tuned. It runs and drives great, the only thing is once in a while it has to crank a while (usually when hot) to start. there is no service light

gMAG

iTrader: (1)

How do the tail pipes look? Is there lots of black soot?
After warm-up, how does the exhaust smell? Does it smell rich?
You might have an exhaust leak before the oxygen sensor, which would cause the oxygen sensor to sense an overly lean condition, which would then cause the computer to tell your injectors to keep adding more gas.
All of these clues will help you to zero in on the real cause(s).
Also, have AutoZone, or your local parts place, scan the computer for codes.
Keep in mind that if you should get an Oxygen sensor code, that it doesn't necessarily mean that the Oxygen sensor is at fault.
Let us know what you find before taking action.

omc8

iTrader: (7)

What area of the country do you live.Northern cold weather states will suffer mileage during the winter.Even though you do not have a SES light , I will bet you find codes when you have it scanned.

gMAG

iTrader: (1)

If the gas tank is 15.5 gals for 98, and you're getting 200 miles, then that would equal about 13 mpg.
As the above poster said, those in the colder areas would see a drop in mileage, due to the cold.
It could be a combination of worn engine parts/rings, and it could be something as common as an inaccurate water temp sensor.
The water temp sensor can be tested quite easily.

s346k

iTrader: (4)

lead foot? my stock 99 car got 27 mpg mixed up to 31 on the highway. I added prob 40whp and 390 gears, it is getting 23ish but still not tuned.this mileage includes multiple highway pulls. do normal tune up stuff and report back..

air filter plugs wires fuel filter clean maf..inflate tires to proper pressure.

HCI2000SS

iTrader: (2)

Back when I had my bone stock 98 Z28 I would average 20-22 city, and 27-28 highway. Now with my 2000 SS and a HCI combo i'm lucky if I pull 17 city and 22-23 highway lol

nastyiroc

iTrader: (9)

@s346k and hci2000ss were both your cars m6 cars? I believe this car is an automatic... Anyone have any automatic mpg stories?

Jorgens

K&n and slp lid only mod 02 LS-1 TA. I get 25-27 city, 26-31 highway. Milage improves if i stick at an octane rating. 91 vs 93. I seem to get a bit better keeping 91 in the tank, but not alwys possible as some stations have 93. Hope that helps... And yes, I go 0-60 in 5.7 sec once and awhile...

HCI2000SS

iTrader: (2)

Yes I have a 6-speed. I don't think the op has stated what his is has he?

s346k

iTrader: (4)

my 2000 a4 z28 got 26 mixed and over 30 on the highway. 273 tho. I did bolt ons 4k stall and 373s and still got 24mixed out of it

Rated Z

That's about what I get with my stock A4 2.73.

aaron_douglas

With LTs, ORY, lid, catback, and Frost tune in an M6 '01 Trans Am I get about 15ish in town and 23-25 on the highway. Little less than I think I should get but I attribute that at least partially to my foot o.O and it having 130k miles on it.