Well, I bought a new SS 6spd for myself in Jacksonville, Fl which is about 7 hours away, and I was like well, perfect way to test gas mileage, Ill just keep the cruise on 75 in 6th gear and test the gas mileage coming home, which should be according to all specs around 26 or 28 at least, right? Well, so I set off heading home and noticed that my gas gauge was moving pretty fast.. After it was all said and done I barely got 300 miles until my gas light came on, THATS only 22 MPG interstate !! What the hell? and my city is even worse! Can someone help me out here, WHAt is everyones normal gas mileage with 6-spd cars? O yea, I ran BP 93 octane on the way home!


Thanks in advance
Landon

 

mileage on car? even been tuned up? could be a million different things....make sure you really top off tank...and so on...Factory plugs tend to lose the little disc which increases the gap, in return you lose gas mileage...

 

Stock Gears? SES light?

 

modded? proper fuel? ie 91 octane or better. Lots of factors to consider for mileage...

 

use cruise controll on the highway and the slower in 6th you go the better. I go from 1st to 4th to 6th around the city. I am in 6th at 35 and i noticed a huge gain in mpg. Also try a search.

 

Dang!!! I just brought LordofChaos's TA home last weekend all the way from Florida and ran 93 all the way home on a 6-speed and the things motor makes 500hp with a decent sized street cam and 3.90 rear gears and got 26mpg cruising over 80mph in 6th the whole way home with getting on it. Every time the trip hit 200 miles there was still a little over half a tank left!!!

 

30mpg 4.10 gears, lid and exhaust. No LT's yet. Thats usually around 60 mph

 

I have no mods what so ever yet. Stock gears 3.42, i used 93 octane, cruise, there is 28k miles on the car, I did get a SES light for 02 sensor bank 1 or something on the way home but I turned it off with my tuner. other then that as of right now I am at half a tank and its only showing 127 miles traveled so far

 

Just do a tuneup, but my city mileage is horrendous as well. im at around 10-12mpg without getting on it and short shifting, skip shifting and any trick imagineable.

 

man it could be NUMEROUS things, clogged fuel filter, bad gas, cheap gas, it could have been tuned before and had a bad tuner, but most of all you said you had a 02 go bad on bank 1 and that is what talks to your computer about a/f and all. If the 02 is bad it may have gone into open loop and open loop means BAD GAS MILEAGE. I bet if you changed the fuel filter, air filter, plugs and wires if it needs it, and fixed your 02 problem you will gain it all back. Those are normal things that should be changed when you buy the car anyways so your maintenance is on your schedule now.

 

Try the dumbest thing of all see if your tire pressure is ok. A few weeks back I took a decent cruise on the highway with my Mach 1 and got 20.5 mpg which is horrible considering I often do better than that all city driving, I usually will get high 20's highway. Come to find out, I had a screw in my tire and pressure was way down something like 18-19lbs and that alone killed my economy by an easy 7-9 mpg.

 

There's no point guessing. You'll have to go over it and replace all the maintenance items, then try again.

Could also be a dragging brake (maybe e-brake).

22 aint THAT bad.

 

its the o2 sensor. when mine went out, 1 or 2, i definatly got worse gas mileage. it is also performance dampening. but only by a hair. but still noticable to me, more up top, once the new o2's got put in. after all it does control your a/f ratio, like platinum ws6 said. you can get them at autozone for like 50 bucks. dont keep turning the code off. also change the oil, for sure. find some amsoil and pay for it. its worth it.

 

What gears are you running in the rearend to be shifting into 6th at 35mph ?

 

If it was sensor 1 bank 1, that's you're problem right there. Sensors 1 on both banks read the exhaust and make changes accordingly. If it was sensor 1, you'll need to replace that 02 sensor.

 

ok ill try to do that this weekend and see what happens, do I need to replace both of them just to be safe. I plan on geting my plugs and wires changed when I do headers in May..So that will be done soon

Landon

 

yea go ahead and change both of them, as when one goes bad the other will usually act up. especially with the miles youve already put on the dying one, not including what was put on it before you drove it home, it would just be a safe bet. and like i said, only a 56$ part at autozone. if you take it to a dealer they will stick you with a $600 dollar fee like i had. if you dont like to work on your car yourself, like me (im 18) , find a trusted shop, only cost me 35 bucks for labor to install.

 

3.42. The LS1 definitely has enough torque to keep the car moving even close to idle speed.

 

22mpg is the most I ever got out of mine when it was stock. Sounds about right to me.

 

i get that combined. all hiway is up close to 30.

6 spd, 3.42s, catback & lid. i also have a 180 stat which lessens the mileage.