Jeep Strokers

Just turning 16,000 miles on my rebuilt 4.0 and noticed my mileage dropping off with the last few tanks of gas. pulled the jeep in the garage and started pulling spark plugs for inspection. They all looked like they should in a good running engine. Shinning a bright flashlight in each spark plug hole I noticed #1 cylinder wall and piston was extremely clean and shinny compared to the rest. I mean I could clearly see the machining marks on the cylinder walls. I pulled the dipstick out to smell for gas in the oil but none detected. Engine has been running well with no problems. Maybe #1 injector not closing all the way?
Thanks for any impute.
Greg

Just a few things you can consider checking

1. swap #1 and #2 injectors and see if the problem moves.
2. check you timing, should be approximately 15 at idle and 35+ above 1500.
3. Swap #1 and #2 wires and see if problem moves.
4. Grab a OBD II tester and check timing and O2 sensor. Timing as above and 02 sensor should bounce between roughly 0.2 and 0.7 volts.

Thank you, I will check that stuff out!