XJ wheeler 916

I know cherokees aint priuses, but why am I getting 9mpg!?
Also whrn I have the ac going and the auto tranny downshifts for power, the belt (i think a.c) makes a LOUD whistle? Kinda emabarassing/annoying

XJ-92

r u lifted or bigger tires cuz im getting 10mpg and most people on here if i remember right are only getting between 9-13 mpg

xjheep92

that doesn't sound right. 9mpg is low.
i have 3" lift, 31s, heavy bumper, winch, roof rack and lights and I'm getting 15/19

I was still getting 12/14 before I did a "full" tune up. spark plugs, cap, rotor, wires, new o2 censor, apn header to replace my cracked one, dynomax cat back exaust, 703 injectors, fuel filter, cleaned intake manifold and throttle body, made a cowl air intake, and new air filter

XJ wheeler 916

My rig is similarly built to yours..so ill try those steps

Rogue4x4

When you did your injectors, did you flash the computer? Made a world of difference on my swap...

brutalxj

Sounds to me like your A/C pump is binding up and close to not tuning at all. This would create a lot of drag on your motor and cause it to work much harder then it should causing your poor mileage.

xjmarc

Gears will make a difference too. When mine was streetable with 35s and 4.56 gears I averaged 16 in town.

xjheep92

When you say "flash" do you mean disconnect the battery and turn the lights on and off

xjmarc

By flash they mean reprogram. If you don't on newer models the computer will just shorten the time the injector fires so it puts out the same ammount of fuel as stock ones.

96rokee

96 xj manual 5speed
4.5 roughcountry long arm
33s with 4.56 locked diffs front and rear.

I get 20MPG on highway at 65mph.

used to get 12. thought noo way...
got some marvels mystery oil put it in my gas tank and my MPG dropped to 8 on that tank. ( cuz it knocked more sediment thru)
then I replaced my fuel filter and ran some sea foam thru my intake and its now 20mpg
and man oh man that fuel filter had alot of sediment in it.

KeatsUSMC

what is sea foam and whats that do ?

sguiffre13

i get somewhere around 10 and im sitting 4.5 inches high with 32s and a pretty big bumper

stereodesigner

im getting 9mpg also
on 6.5 lift and 35s

1996XJSport

I'm getting 14 mpg with a 3 inch lift, 31s, Flowmaster 40, Roof rack, Roof mounted spare, Jerry can, Shovel, lights, Solid steel prerunner bumper, etc.

I haven't really done a "full" tune up though. I've just cleaned my throttle body, Replaced the spark plugs with champion coppers, Replaced the plug wires with MSD 8mm's, and seafoamed it. I still need to replace my O2 sensors, do my neon injector swap (I have the injectors, but don't have the time to swap yet), put my snorkel in, and get a bored TB.

RANG7R

Should've got the higher quality plugs to go wit the wires and your wires are no better without the cap and button. I got a Mopar performance set from the local dodge dealer (cap, rotor, wires and plugs) for like $110 Canadian. I think that was mechanic pricing though.

Is there a better o2 sensor to buy? Or just go with a typical after market one?

I'm waiting for my Rough Country 3" lift and I got 31's on rims out back for my XJ and just wondering what all I can do to keep the mpg decent. I need to replace my manifold (cracked) and I was looking at an ebay header, worth while?

Any other tips I'd love to hear it.