Hear lately I've noticed my jeep has been getting extremely bad gas mileage such as about 8-11 mpg. Used to before I went up to 31s I was on 30s before it was getting about 17 18. It's got a new 02 NTK new sparks and newish spark plug wires replaced within 2 years any tips to help my gas mileage would be well appreciated and it also seems to have a miss I'm not sure on what cylinder or if it does at all it just seems to idle a little funny