My '00 Disco2 gets an average of 12.2MPG (US) on Premium (91). I've changed the air filter, and MAF. It has new plugs (and wires) about 1 year ago.

12.2 MPG seems low even for this truck. I would expect 13-14 MPEG.
Any suggestions on what else to check?

 

How many miles? If you are over 90K, change out all 4 O2 sensors. What plugs and wires are you running? Have you ever done an induction cleaning?

 

Dont overlook the obvious, check tire pressure too.
Do you have a roof rack? A load of brinks in the back?
I am betting on worn out O2 sensors.

 

yeah what they said

 

Run your tires at 40 pounds all the way around, get your foot out of the throttle.
Asked already mentioned or asked, what size tires are you running, do you have a roof rack, what brand of plugs and wires are you using, have you ever tried an induction cleaning and a can of B&G's 44K?

 

Why all 4. Only the front to really matter (At least on a D1). I know of a D2 that had a code and replaced only 1 O2 sensor and increased his gas milage by 100 miles on the tank. And if there are no codes. Of course a D2 O2 sensor is about half the cost of a D1.

The Goose

 

This is after I changed my O2 sensor.. Prior to doing so, I was only getting about 200-215 miles per tank. Changing it out made a huge difference..

Regards,

 

You're probably going to get yelled at for running your tank down to the gas light...

 

yes. all that money you saved on gas will go to **** if you keep running your tank that low. you will burn out your fuel pump and need to replace it. don't let it get that low in the future.

 

lol, thanks for the forewarning! its not something i do all of the time, I simply wanted to see how far I could go before the light came on, and I got the answer! I will however make sure to do my best and keep it above the 1/4 mark in the future..

Thanks again,