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ok someone talk to me....MPG?

trashedxj

NAXJA Member # 1386
Location
virginia
ok so ive been calculating my gas milage and i found that i get and average between 12.7-14.56 mpg. im running small tiny 31's with stock gearing! whats my jeeps issue? i know i should get more than this. heres a list of problems the jeep has, you all run down the list and tell me whats most importants to get done.
bad o2 censor
cracked header
leaking cat
have never changed the spark plugs in the 2 years i've owned my 94'
nor have i changed plug wires, rotor, or cap
possibly could do a tranny flush
my homade intake has a 2" hole in the cone filter.

well that about does it. its official im a tard whom abuses the xj(i know i know someone slap me with a fish) i love my xj but funds are tight cause i cant find a job. but somethings got to be done i cant take it anymore. i throw 10 bucks in just to run and grab ciggs and come back home on empty!
 
there are a number of theads on this site that tells u how to check ur sensors, before u replace, sheck ur sensors and go from there.
 
Quit smoking, then you'll have more money to fix it up!:twak: Plugs, wires, cap & rotor would be a good start.
 
trashedxj said:
bad o2 censor
cracked header
leaking cat
have never changed the spark plugs in the 2 years i've owned my 94'
nor have i changed plug wires, rotor, or cap
possibly could do a tranny flush
my homade intake has a 2" hole in the cone filter.


hmmm....

i would start by running through this list...
 
man, sounds like your sh*t can use an overall tune up. in the last 2 months i replaced my o2 sensor, did a general tune up, spark plugs, rotor, distr. cap , wires etc.... replaced my cracked manifold with aftermarket, cleaned out the fuel system and looks like i am getting more than 14 mpg at any given time. my next upgrade is the taurus 3 wire fan with thermo switch. that'll reduse the drag from the oem mechanical fan and hopefully save some more gas. anything to save some gas and get more mpgs these days. another reason i had to do the tune up was because i had a smog test to pass.
 
i was in a similar boat a few months back and i went through the tune up list checked my sensors and finally said screw it because everything was either new or fine. so next was the gears... i had the following 4.0 aw4 with 31's and not a heavy foot and 3.55's and got 10 mpg no matter what i was doing. next i went and got 4.10's (big mistake) because i thought i was not going to get bigger tires for a while :banghead: and my mpg went from 10 to 16-17 mixed driving and around town about 14.5 - 15 mpg. if you are thinking at all to run 33's get the 4.56 now and stay away from the 4.10's or you will end up in the same boat i am in wanting 33's but don't want to lose my mpg i have now. personally i noticed the biggest increase from the regear inho. hope this helps
 
Those mpg numbers sound about like mine. I'm running 31,s with 3.55's, on a 2000. Based on you list the first thing I would fix is the filter. Even if you have to barrow ten dollors off of somebody, and reinstall the stock aribox with a new filter.
 
POSXJGuy said:
man, sounds like your sh*t can use an overall tune up. in the last 2 months i replaced my o2 sensor, did a general tune up, spark plugs, rotor, distr. cap , wires etc.... replaced my cracked manifold with aftermarket, cleaned out the fuel system and looks like i am getting more than 14 mpg at any given time. my next upgrade is the taurus 3 wire fan with thermo switch. that'll reduse the drag from the oem mechanical fan and hopefully save some more gas. anything to save some gas and get more mpgs these days. another reason i had to do the tune up was because i had a smog test to pass.

POSXJGuy,
Can you tell me a little more about the Taurus fan? What are the other benefits for swithching to it and where did you heard about it?
Thanks
Boris
 
Ouch! 14 mpg hurts, I'm getting 17 in town with 30's and 4.10 gears, 22 highway. Plugs, cap/rotor, wires and a good TB and upper cylinder cleaning would help. Then after the basics are done check the more complicated stuff like the sensors.
 
Like was already said....If you know those things are bad go through your list and replace them.

Also, what gears, tranny etc? I was getting terrible mileage with my 31s and stock gears.
 
trashedxj said:
bad o2 censor
cracked header
leaking cat
have never changed the spark plugs in the 2 years i've owned my 94'
nor have i changed plug wires, rotor, or cap
possibly could do a tranny flush
my homade intake has a 2" hole in the cone filter.

plugs first
wires at the same time
roter and cap at the same time

o2 sensor second.

air filter third

Injector cleanter fourth

If don't change oil + filter on regular basis use shotgun to put jeep out of misery

Gears are very important. if you are on 31's you should have 4.10's
If you have a 5speed you can get away with 3.55's from an auto. its cheep and easy to swap from a junk yard.

my 5 speed with 3.55's and 31's gets 18 round town 22hwy give or take.

if your cat leaks fix it or cut it out. it can also cause bad mpg.

also...
I hate to say it...but i have to agree with
Quit smoking, then you'll have more money to fix it up!:twak: Plugs, wires, cap & rotor would be a good start.
I have a much better way to spend my money... like my 33's i am getting soon... think about it...
 
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