bigvig

Although I read this forum every month or so Ive never posted. Never had anything to add really, but I enjoy reading what others are doing to their Jeeps. With that said, my XJ is getting up in years (10 going on 11 to be exact) and she is SUCKIN' the gas, so its time to do something about it:

I desperately need a tune up, no problem there, Ive done many, but I also need an exhaust and Id like to give her (Goldy) a tune up with some decent parts and put a stainless exhaust on her that will give me some performance bonuses.

So, what can I do with tune up parts and an exhaust that will give me some better mileage and a little more performance? I appreciate any help in advance. Thanks, Duane

1999 Cherokee Sport 4.0 with 134 thousand-something miles

xj17901

Since its getting up there in years, you may as well flush out your systems. I flushed em all and tried to get some of the gunk out of there. I just have to replace an exhaust manifold and put an o2 sensor in and shes good to go. It wouldnt hurt to run some injector cleaner and all the little things too. Not guaranteeing its going to make you run good mileage, but its nice to start somewhat fresh.

4.0cherokee

You can read my write up and what is going on with my 99 xj that is also gold. We are having some of the same problems. https://www.cherokeeforum.com/f2/bad...x2/#post324835

bigvig

I appreciate the responses. I just read through that entire thread and I feel sorry for you guys. Im nowhere near that bad, Im getting about 13-16 city/backroads (heavy footed) and maybe 15-18 highway (again, depending on if Im doing 70 or 85). I just hate that I know people who are getting 20-24mpg with their XJ's and Wranglers with a few mods. I just want to boost the power a little and get a few more mpg's. There isnt anything "wrong" with my XJ (knock on wood) other than I wish it got better mileage. I keep her alligned and she is all stock, including tires.

So I guess a better question would be, when doing a tune up, are there some really good plugs and wires I should go with over others? How about the cap and button? Throttle body spacer do anything to help? A good cat back exhaust? Thanks again.

4.0cherokee

Plugs I would go with champions. Just the cheap copper top champions. Wires I just went and picked those up for autozone while i was getting my plugs. TB spacer from what I have heard is that unless you are just ringing it out and staying in high rpms a lot it wont provide that much improvement. "Just what I have heard no person experience". Once again i got the cap and button at the zone and mine all work like they are suppose to. I cant tell what they would do for a system that was running better than mine, but i noticed it runs a little better.