So i've had my XJ for about 2-3 months now and i love it. My only problem with it is that i get terrible gas mileage, i expected it to not be the best since it's bigger than the little ricer i had before. but the last time i checked my mpg, i was getting about 10-12 mpg. i looked up what it should be online and it claims i should be getting about 14-18 mpg.

is this right? or is what i'm getting pretty common for my XJ? it's a 91 limited by the way.

and just for starters before someone says it, i do need to do a tune up, i haven't done that yet. but will that make my mpg go up to about 14-18mpg? if not, what else can i do to get better mileage?

this car is my commuter, so it'd just be nice to get an idea or some tips on what i can do to make it better.
would small modifications make a difference? such as an intake or something? i don't know too much about cars but i'm ready to explore my car!

 

I know you're new and all. but the first thing you gotta learn how to use is the search function. there's about a million threads about gas mileage.
but mostly, people will tell you to buy a different car.
personally, I'm gonna do this http://www.ls1tech.com/forums/genera...-your-car.html
other than that it's just having a clean system and good driving habits.
people will also tell you neon injectors, exhaust upgrades and blah blahhhhh. I wouldnt really bother with a goose chase for better gas in an xj

https://www.cherokeeforum.com/f2/xj-gas-mileage-619/
https://www.cherokeeforum.com/f2/tip...mileage-23736/
https://www.cherokeeforum.com/f59/ge...ileage-102840/

 

There is ALOT you can do. Probably more than I can think to list. A google search would help. But here are a few tips for you.

-change your driving habits
-tire pressure
-type of tire (they design tires for mpg now)
- air filter
- fuel filter
- fuel pump
- fuel injectors
- fuel rails
- spark plugs
- spark plug wires
- clogged cat
- wheel weight
- your vehicle EDC

That's about all I can think of for now. Google hyper miling. Good luck!

 

yeah, i've tried using it before, and i didn't quite get the right results i was hoping for. but thanks for sending me these links, it was helpful. a lot of people are saying the o2 sensor makes the biggest difference. so after i do a tune up, i'm going to look into changing that.

 

thanks!

 

In addition to what nate already listed, get a new upstream o2 sensor and clean your throttle body.

 

Do what i do, Buy a 4 banger beater. I use it for my work car. I figure i save about $1400-$1600 a year. Just going to work and back.

 

how would i test the 02 sensor and is there an upgrade ?

 

Start with the tune-up first. New Champion Copper or NGK spark plugs, good ignition wires like the ones from Napa, new dizzy cap and rotor with brass, not aluminum, terminals. Fuel filter and clean the throttle body as suggested. Basics....

 

that skinny petal on the way to the right...dont push it so hard

 

Looks ya all covered it pretty good the only things I'd add is, alignment, dragging brakes, reduce the weight of the stuff you may have in it, Gearing if other than stock tire size, tire width.

 

What kind of driving? Short trips and city driving can give you those numbers.

 

Cleaning out the intake is a biggy, its amazing how nasty it can get. I assume you have an auto, try adjusting the kick down cable and resetting the shift points. This help with my gf's because before it would always want to stay around 2500 rpms while accelerating but we got it to start shifting around 2k. I have a manual XJ so I never drop below 16mpg