Is 12mpg normal?

[Hahnsb2]

Right now My BII has 28" tires and got an average tank of 12 mpg with the lowest I have seen was 11mpg. I have read that the 2.9L get 17-20mpg. Are these people full of $*** or is there something going on with mine?
Its an automatic, fuel injected. The reason Im asking is because I want to add 31's and I think my gear ratio will be 3.07. Just trying to figure out how to get the most out of the mpg.

How are you measuring gas milage? I really hope you aren't basing it off the gas gauge and how big you think the tank is. You should be getting at least 15MPG, I drive mine like I rented it and still manage 15MPG.

 

[MAKG]

imgetting 16-18 mpg with my 2.9, pushing 33x12.50 swomps and 3.73 gears. if i was you. punch out the honey come shit in side the cats, if that dont do it, do a tune up. NEW= cap/rotor , plugs and wires, oil and filter change.

And enjoy the $2500 fine and the POS you just made.

Punching out the cat is a BAD IDEA. You gain absolutely nothing (more to the point, you LOSE peak power) and make a lot of gunk for the rest of us to breathe.

Why do you think it costs you mileage to pump through a cat? You do know why they flare out, right?

 

[mkpecor]

did i say i did it to mine NO. if the cats were the prob after you did that then you would know to get new ones.

 

[mkpecor]

i can run with no cats if i wanted to. i dont have the emission test's here in black diamond.

 

[gotmudd]

did i say i did it to mine NO. if the cats were the prob after you did that then you would know to get new ones.

 

[WhiteBroncoII2WD]

You should be getting better than 12 mpg. Put the time in to do the maintenance items; plugs, wires, cap, new air filter and an oil change and if you still feel there's problems fellow Allen's steps.

the maintenance items are still the cheapest place to start and at least then you can ruel them out if the problem persist

 

[88gt]

hey man, i have a 2.9 in my 88 that got 13 mpg consistantly no matter haw hard or easy i drove, and it tuned out that the battery cables were corroded thru and hardly passing any electricity, soon as i changed that, i got back up to 20mpg driving like the mad-man that i am, so thats a easy 10-20 dollar fix, i would suggest starting there. trying anything with exhaust right off the bad could mean a new $500 plus exhaust and .1mpg better, start cheap and work your way up the line.