My 1990 YJ 4.2 is only getting 12.5 miles per gallon. It has been converted from a carbureted to fuel injection?
The Islander either had a 2.5 or 4.0 eh? You'll never get 20 mpg like those two engines from a 258 IMO. Does it seem rich? what gears?,what tire size?
I get a little over 13 mpg in my ‘95. Thought I would correct my speedometer error by changing my tires from 27’s to 28’s, which it did, but now I pretty much don’t need 5th gear, and it’s a 4.0. I checked my mileage on a 160 mile round trip to Lincoln, in 4th gear, and calculated 16 mpg. But driving around town, back and forth to work, etc, 13 mpg. I suspect 3.07’s for my gear ratio.