Havent had time to read all 80 plus post so not sure if this has been posted yet,

Try Ethenol Free gas. On the first tank with Ethenol free gas i got 1.5 MPG more.

 

Warthog,
Love the A-10 avatar!
2 door and 4 door have same wheelbase and overall length.

 

I have a 89 cherokee with 30x9.5 on it. I get 22-23mpg on the freeway.

I have installed a air intake, full sythetic oil in the motor, transmission, front and rear diffs. Tune up with a cap, rotor, wires, and plugs. I had my injectors cleaned, and every 3rd tank i run a bottle of seafoam through with the gas.

I have been getting 22-23 on the freeway for a couple months now.

 

Thanks,
You should see those over head every now and then where your at

 

I forgot that a long time ago when I first got the jeep I put in an entirely new ignition system except for the coil. I put in the plat +2 bosh plugs in and it was way better then what I had before. They are still going strong. I installed it at 140k i'm at 212k now.

Didn't know that the 2 vs 4 was the same.

 

I did a tune up right after I got the jeep, it helped some.

I gott run like 28psi with my 31x12.5s or the dont wear evenly. I think thats hurting me some


Changing your fuel filter that much is throwing away money, its def not gettin dirty that fast and a dirty filter usually helps gas milage.

Where is the air temp sender your talking bout? ten years of dirty and dust its prolly pretty dirty. I should prolly clean my MAF off too.

 

In my 93 XJ Sport 4.0 (257k miles) I get 18 back and forth to work (backroads) and an honest 20+ on the highway at 60 if I keep my foot out of it. It's stock except for a K&N, TB spacer and I pulled out that air restrictor in the intake. 6 ply all terrain 215/75-15's.

Best I EVER got was 23 because we followed a snowplow at 40mph for about 40-50 miles on a flat hwy (I was in overdrive) in 2WD.

My .02:
- Take it easy on the right foot. Get this: The slower you go (in OD) the better your mileage. Incredible.
- Get it into OD as soon as you can with reasonable acceleration. The 4.0 and AW4 seem to hit this at about 43mph. I'd be curious to hear other guys input on this.
- Keep it tuned. Tires make a huge diference. Use tier 1 fuel (I use 76 plus).
- I have a friend who's tried Hydrogen injection but his truck is a mess and he has yet to get it running properly. There must be some threads here about this.

 

What is this restrictor?

Also what is the idle speed in OD at 60mph? My cherokee was around 2k.

 

They are an extreamly rare sight... I've only seen them once... frind says he's seen them once...
Pretty easy to tell when a military jet is in the air tho... noise... love it.

 

The restrictor is piece of plastic they put in the air intake just off the airbox outlet. The intent was (I think) to increase air velocity and create a laminar airflow. I pulled it out and got about .5-1 better mpg - but I also added a tornado-type turbulence device in it's place. This is the opposite of the intended effect of the restrictor horn, but on a 250k engine the plugs last longer (no fouling) and I better mpg.

My XJ runs 1850RPM at 60mph. Stock Dana 35.

 

I can tell you where it is. when you are looking at the I6 head on. Look towards the back channel of the intake manifold. You will see a 1/4" plug with an electrical connection. You can replace it for 20 bucks or you can get electrical degreaser from the box store for 3 bucks. Its basically a diode and when its clean it should be a shiny green. Using a diode is an old cheap trick to measure air temp since the temp of the diode allows more current to flow when its warmer or colder. You could go to the yard and go pull one. Then you can drill a hole and just self thread the new one into your air box (behind the air filter. Just make sure to pull a 3rd air temp sensor so you have a connector that you can just plug in and out of the harness. Because your making a 3 ft piggy to the air temp sensor to the air box. Leave the old one in during the summer as a plug. During the summer you want it connected to the air box. During winter you want it at the factory location. So just pull 2 from a yard and clean them and get your #14 wire out.

I tried the air restrictor thing. Its basically a plastic funnel connected to the air box housing. You can pull it out, I didn't notice anything, so I just put it back. You really need to do more to see the change effects. Like you could put a throttle body spacer on. Or you could extend the length of the intake hose. The longer the passage you'll get the similiar effects of the spacer and saving yourself a half hr from bolting it on. The suzuki sx4 manipulate the length of its air tube to change its power output.

 

also when you see a light turn red way in front of you slow down really early so you can slowly roll and preserve some of your momentum, and with some luck and timing, the light will change before you get there. i have a 89 xj wagoneer with 31"s and 3.55 gears and if i drive it normal (and by normal i mean like all the other maniacs on the road) i get like 13-14mpg but if go easy on the acceleration and do that slow roll thing i get about 18-19 mpg cause the bulk of your fuel is used when getting up to speed so avoid stopping at all costs to preserve that momentum! (nothing illegal right fellas... ).google hypermiling

 

I use to use the bosch platinums, but I fouled them out twice as much as a set of 2 dollar each autolites

 

Stock 1992..2WD..2door..5 speed.4.0...General Altimax tires 225/70's pumped up to 45 psi..slight front end lowering 1 inch... rear up same amount.. modest lip air dam... this slight adjustment really does improve the airflow over the body..the slight tilt to the brick body does cut air drag at highway speeds..and that 3:07 rear end with that 22% O/D it works out to a 2:39 final drive... run 15/50 Mobil 1 syn...gets real hot in Texas..this oil fits the bill..and a shot of 8oz German Liqui-Moly oil additive in engine and their manual trans moly additive in gearbox and rearend.I know for a fact that Mercedes and Porsche use this same additive in their manual/rear ends.Always get 21-23 to work...60 mph .mostly highway. On long trips interstate just checked out twice this month at 27.5 at 60-65...above 75 the mileage does dip to 21-22... RPM is 1900 at 70 MPH...very easy ..quiet cruising...straight street Jeep...First post last year had better mileage posted but found out I was not filling tank up to top ...gave unreal mileage figures but now after a year and half driving I can post these corrected stats...and the Liqui-Moly has taken away the classic ticking at idle the 4.0 's seem to have..runs smooooth....201000 miles..nice

 

i use E3 diamond fire plugs, and they work awesome