Poor gas mileage

Tiny
JAMIELEIGH
  • 2002 JEEP LIBERTY

Engine Performance problem 6 cyl Four Wheel Drive Automatic 66000 miles

I have had my jeep for a little over 4 years now on average I was getting 300-320 miles on a tank of gas. About 6 months ago I noticed the gas mileage was getting worse. I thought it was just from using my 4 wheel drive but when I no longer used my 4 wheel drive I was still only getting 200 miles on a tank of gas. I have never had any issues with my jeep before.

Why is my gas mileage getting worse? What can I do to fix it?

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Tuesday, September 16th, 2008 AT 3:47 PM

14 Replies

Tiny
JACK42
  • MEMBER

Tires are a big thief of mileage. Have you noticed any difference in the performance of the Jeep? HAve you had the filter repalced? It looks like it has the fuel pressure regulator built into it, if the reg is having a problem, this can cause a rich condition and more fuel consumption

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Wednesday, September 17th, 2008 AT 2:32 PM
Tiny
JAMIELEIGH
  • MEMBER

No, other than the gas mileage being worse my Jeep runs GREAT!
So then are you saying I should get the fuel system checked? Like fuel injection/filter/etc?
Would getting a tune-up help the problem at all?

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Wednesday, September 17th, 2008 AT 6:37 PM
Tiny
JACK42
  • MEMBER

At 66k it might be a little early, but I guess it wouldn't hurt. Be sure the tire pressures are up to spec and yes, have the fuel pressure checked to see if the regulator is stuck open giving it too much fuel pressure. This will make it have great power, but poor mileage.

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Wednesday, September 17th, 2008 AT 7:04 PM
Tiny
PGORSKY
  • MEMBER

I'm suprised nobody mentioned a stuck/dragging brake caliper. It is possible.

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Thursday, January 22nd, 2009 AT 6:08 PM
Tiny
JACK42
  • MEMBER

Anything is possible, stuck brakes usually cause odor from the pad burning

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Friday, January 23rd, 2009 AT 7:06 AM
Tiny
PGORSKY
  • MEMBER

Well, that's why I wrote "stuck/dragging" If they are dragging they may not smell but will reduce mpg

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Sunday, January 25th, 2009 AT 7:46 PM
Tiny
JACK42
  • MEMBER

Well, dragging is friction, which creates pad wear, which makes odor

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Sunday, January 25th, 2009 AT 10:06 PM
Tiny
JOHNP139
  • MEMBER

I have been searching for a simple answer to this question without any luck. 2004 Jeep Liberty 3.6LVS 85kmi is getting 10.8mpg. I am sure this is an air intake temperature sensor fuel mixture problem. I changed the intake sensor and now holding at 12.1mpg. Looking for some kind of engine control unit computer solution to tweak the fuel mixture. I used to get 20mpg on the highway for years, even hipper-mileage with 40+psi tires. My original muffler started to leak at the seams got noisy. The engine was bogging out, I had the O2 sensor changed at the dealer. That did not solve the problem. I replaced the cat back exhaust with "MBRP CAT BACK SINGLE SIDE, T409 02-07 JEEP LIBERTY" @ $379. I wonder if the straight pipe having less restriction is throwing off the computer. This is about the same effect as the leaky muffler. Forget about the brakes, tires all the rest; not the cause.

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Wednesday, July 5th, 2017 AT 12:59 PM
Tiny
2CARPROS KEN
  • ADMIN
  • 9,508 POSTS

Hello,

Bad mileage is a sign the MAF sensor needs to be cleaned or replaced. Here are a couple of guide to ehlp you get the problem fixed.

https://www.2carpros.com/articles/mass-air-flow-service

and

https://www.2carpros.com/articles/how-to-replace-a-mass-air-flow-sensor-maf

Please let us know what happens.

Cheers, Ken

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Friday, July 7th, 2017 AT 12:39 PM
Tiny
DEDIPHIL
  • 2003 JEEP LIBERTY
  • 100,000 MILES

I bought one used jeep liberty 2003 (petrol), I was thinking that with 4 cylinders of 2.4L The fuel consumption will be normal but the average consumption is 28 L / 100 km.

The Engine is it faulty?
Please what to do to reduce the fuel consumption?

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Friday, July 7th, 2017 AT 7:34 PM (Merged)
Tiny
MERLIN2021
  • EXPERT
  • 17,543 POSTS

02 sensors are 100,000 mile parts and play a major role in fuel economy, have them checked with a scantool. Also mass airflow sensor, ect(engine temp. Sensor) we need to figure out if the pcm is switching to open. Loop operation.

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Friday, July 7th, 2017 AT 7:34 PM (Merged)
Tiny
WRENCHTECH
  • EXPERT
  • 20,814 POSTS

Are you sure that is correct? That converts to about 8MPG and that is really extreme. You likely have a check engine light coming on so you need to have to codes read and go from there.

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Friday, July 7th, 2017 AT 7:34 PM (Merged)
Tiny
MANFROMNORTH40
  • 2006 JEEP LIBERTY

Engine Performance problem
2006 Jeep Liberty 6 cyl Four Wheel Drive Automatic 36,000 miles

My wife's Jeep Liberty has normally been getting around 20 MPG. She filled the tank the other night and checked her mileage, she got around 16 MPG. Why did the mileage drop so much so fast? There are no check engine lights on and it seems to be running ok. She did say that it seems more sluggish than it normally is.

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Friday, July 7th, 2017 AT 7:34 PM (Merged)
Tiny
JACOBANDNICKOLAS
  • EXPERT
  • 68,268 POSTS

If the check engine light came on, it would be easy to diagnose. However, without that being on, there are so many factors that could cause it, I don't know where to start. Did her driving habbits change or the places she normally drives change? Also, has there been a loss of power? It could even be a catylatic converter starting to plug.

Check those out and see if you can find anything out of the ordinary.

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Friday, July 7th, 2017 AT 7:34 PM (Merged)

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