If your driving around town normally at WOT then I think we have found teh problem

 

also try taking your 1st gear up to your normal 2500-300 and skipping 2nd and going straight to 3rd, its easier on your left leg and saves your clutch a little too from the reduced gear change

 

That really isnt that bad of mileage.... If you wanted good MPG why'd you buy a Mustang to begin with? Also your traction control thing sounds like it could be a blown fuse? Unless somebody turned it off permanently.

 

thats about the same as what i get when my car doesn't see the highway very much.

 

Whens ur next oil change it might be up givin you worse mpgs

 

depending on the weather you are in, it will also determine mileage. colder climates will get worse mileage than warmer climates. thats why i look forward to it warming up here in new england. besides the fact im sick of the snow.

 

look in your owners manual, it says "for best fuel economy" shift at:
11, 19, 30 and then 5th at 40 mph

 

i get 14mpg... with lightly modded gt.

 

this 1/2 tank stuff cracks me up...

Why?

On my car I go through the first half tank fast.

The second half always lasts longer... I'd just guess the last 1/4 tank goes twice as far as the first 1/4 tank.

Try to test with a whole FULL tank...

 

i just filled up my tank... i'll put u guys up to date mile by mile =D