give it a fresh tune up. on mine all i have to do is change the plugs, i have the coils on plugs...
or try a fuel treatment... i was getting 13, just tried a prodect name called BG Products Inc. look them up on the web,
BG 44K® Power Enhancer®
that is what i just used in my last tank. i still got 13, but this tank i am at 200 miles and have a 1/4 tank left.
1977 Cherokee ChiefEdelbrock 1406, 33X12.50, front 1.5 inch shackle lift. AMC 360, th400 Quadra-Trac
2002 wrangler, stock 4.0, auto, 33X12.50 maxis buckshot, AEV Highline Body kit, Ford 9 inch rear end.
Soon to come mods: 4" full traction lift, 4.56 gears, 35X10.50R15 boggers, 35X12.50 cooper st tires, spooled rear end, and much more.