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qbny94 09-01-2011 10:28 AM

Need better fuel economy
I've been noticing that after watching my gas gauge i've noticed i am getting about 11 miles to the gallon. I just got my spark plugs replaced so that cant be it. Does anybody know why im getting such bad mileage? Also, are there any after market parts i can get for better fuel economy on my WJ? I know its a JEEP and there not good on gas but it should still be getting around 15-16 city not 10-11... hope there's something i can do!

Thanks All:)

TJXJWJ 09-01-2011 10:49 AM

Re: Need better fuel economy
You may find this helpful...even though we're not WK's...

1st things 1st...what motor, year, condition, etc? Any existing mods?

qbny94 09-01-2011 10:52 AM

Re: Need better fuel economy
i believe its a 4.0 L V6 year 2000 WJ and no mods mechanically. I've had the spark plugs replaced very recently due to corrosion. But i use it mostly around town and dont drive it much and i filled up monday night and am almost at half a tank.. something not right there and no signs of fuel leakage

TJXJWJ 09-01-2011 11:08 AM

Re: Need better fuel economy
The inline 6 isn't known for it's economy...that's for sure. Are the tires at proper inflation? Are you heavy on the gas pedal? Air filter in good shape? Fluids kept up? A throttle body cleaning is always an easy job and worthwhile. How are your brakes? Do you maybe have a dragging brake pad? It could be a TON of things, so let's eliminate the easy stuff first. I had a 98 XJ with the 4.0L and it got right around 15mpg regardless of city or highway. I'd say you could do a lot better than 10-11. Are the tires the correct size or are they oversized mud tires or something?

dmlong47 09-01-2011 11:20 AM

Re: Need better fuel economy
try a fuel injector cleaner

qbny94 09-01-2011 11:29 AM

Re: Need better fuel economy
The tires are at proper inflation. I try to coast as much as possible. Air Filter was replaced a few months ago. Fluids and Oil changes have all been kept up to date. And as for brakes they seem fine and have meaty brake pads still. Maybe if i get a Cool Intake air system or maybe my o2 sensor? not to sure i have a 114,000 miles on my WJ and tires are stock size

2004wjmedic 09-01-2011 12:03 PM

Re: Need better fuel economy
My dads 99' WJ with selec-trac and the 4.0 averages 20-21 and it has 270,00 original miles on the clock. Good luck!

TJXJWJ 09-01-2011 12:29 PM

Re: Need better fuel economy
It could be lazy 02 sensors...or so I've heard. I've been contemplating doing mine now, but it takes 4 of them and I will go broke in the process.

A cold air intake would help, but barely. That's not your should be doing better than that without a cold air intake. Any squeaks or noises coming from the wheels? Maybe you've got some worn components or need an alignment. Those can contribute to crappy economy too. A clogged converter could also be part of the problem. Do you hear any metallic rattling in the exhaust?

qbny94 09-01-2011 12:46 PM

Re: Need better fuel economy
when i had my spark plugs replaced last week the mechanics said the jeep was mechanically sound and my tire pressure and wheel alighment are fine. And i'm not hearing any weird abnormal noises. I have no ideas what it can be and i'm willing to put money into it to fix it. Filling up my tank every week for only local town driving is insane. Almost every where i drive is within 10 minutes from my home.

99PlatinumWJ 09-01-2011 12:48 PM

Re: Need better fuel economy
im getting about 10-12 city.. it doesnt help that i drive like 3-5 miles at a time to work or school and its all stop and go or that my foot it a little heavy either lol i replaced the spark plugs, oil is changed every 3 months or less, check my tires every other week, replaced both o2 sensors also.. i might change the fuel filter too, maybe it will help. and i need an alignment!
highway i can get 17-18 mpg doing 75 mph, probably 20 if i did 65 lol

TJXJWJ 09-01-2011 12:52 PM

Re: Need better fuel economy
Mechanics can say lots of things. Have you yourself checked the air filter and the tires? Just trying to rule things out. Lots of people on here swear by a treatment called "seafoam" you can get from any local autopars store to clean things up...that may help you too. You're not getting any idiot lights/check engine, right? Does your Jeep have an EVIC (computer overhead by the rearview mirrors with map lights built in)? If so, is that where you're getting your MPG estimate?

qbny94 09-01-2011 12:54 PM

Re: Need better fuel economy
lol i feel your pain!!! i have no idea what could be causing it something is obviously wrong here with our gas mileage. And now with school i'm going to be driving it everyday i mean my school is only 10 mins away but still..

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