98 Classic keeps blowing IOD fuse. Since fuse has blown better mpg?

About a month ago my fuse popped for my gauges, radio, power locks, interior lights and not sure what else is on the IOD circuit. Jeep runs fine and everything else seems to be working okay. I mainly drive my jeep to and from work about 100 miles a week. I have gotten terrible gas mileage for years around 11mpg. Since my fuse has been blown I stop and get gas weekly as I did before, same driving distances as it's a routine. My jeep has been taking less gas to fill up about 3.5 gallons as apposed to the 9.5gallons pre blown fuse. Any ideas? Does anyone has a schematic they could send me of the IOD fuse circuit for a 98 classic auto 4.0? Any input is appreciated.

If you get 11mpg hwy with a stock or nearly stock XJ, you have an exhaust manifold leak, or O2 sensor issues.

Why the IOD popped or what effect it would have on mpg's is unknown, and secondary to the manifold leak/O2 sensor issues.