If you're only driving a few miles, chances are the car isn't getting to operating temperatures, when it's cold, then the ecm makes the engine run rich to light off the cats, that's supposed to be good for emissions, but for those with short drives it's very bad for mileage.

 

I have an 03 6mt and its all in how you drive. B4 I was consistently getting aroung 16-18mpg city but 25mpg highway (80mph). In the past month or two I tried really watching how I drive and I noticed that shifting b4 or at 2k rpm and anticipating stops and coasting I can get 25mph city.

From my experience it seems as if gas mileage on our cars depend more on how high the revs are and not in how much throttle is used. From my tests gas consumption was higher when...shifting around 3k rpm but using little throttle...and lower when...shifting around 2k rpm but using more throttle...weird.

 

does having a near bald tire low your mpg?

 

I have 3mm left in the rear and get 25mpg city. It'll affect the mpg but what really matters is when you shift, coasting, and using the brakes less.

 

Are u guys using premium gas?? Have you done the basics?? Clean air filter/
clean intake manifold and intake valves(efi service) the self learn cont
on the ecu may need to be reset/ meaning if u drice the car aggressively
the ecu learns that you drive the car that way and may start running rich//