Jeep Wrangler Forum banner

Bad Gas Mileage

21K views 12 replies 9 participants last post by  Scott B. 
#1 ·
So I'm wondering what might be causing my jeep to get such bag gas mileage. I know your probably thinking its a jeep they don't get good mpg. But my Jeep is getting right around 10 mpg which is almost as bad a my last vehicle that had a v8.
 
#3 ·
I have no clue when the last tune up was done on my jeep. I plan on doing an oil change this week. But for some reason my jeep takes a long time to crank over I was thinking that this might be causing the bad gas mileage. Or it might be the starter, any thoughts?
 
#4 ·
Im getting anywhere from 10-15mpg in my completely stock jeep just because I do a lot of city driving and I have a heavy foot. Ive notice that if i change my driving style I can get a couple more mpg per tank.
 
#6 ·
My auto 06 Rubie with 4 inch lift and 33X12.5 tires gets 15 MPG consistently, mixed driving, but in the winter it will drop to 14ish. On strictly highway, running a steady 60 I can do 19 MPG.

J
 
#7 ·
My auto 06 Rubie with 4 inch lift and 33X12.5 tires gets 15 MPG consistently, mixed driving, but in the winter it will drop to 14ish. On strictly highway, running a steady 60 I can do 19 MPG.

J
Mine is auto as well, you are also geared properly already. You have 4.10 I have 3.73. So you will get better gas milage because of that. 33x1250 with 3.73 auto isn't good for mpg
 
#8 ·
Taking a long time to start after sitting a long time is normally caused by a bad fuel pump having let the fuel drain down out of the engine. The additional time to start is how long the pump needs to get the fuel back up to the fuel rail.

Did the mpg get worse over a short period of time? Do you ever smell fuel? If yes to either or both of those, I'd suspect a bad upstream 02 sensor. A bad 02 sensor can fool the computer into setting the air-fuel mixture to full rich.
 
#9 ·
Well I am getting about 100 out of one tank right now... Can sometimes push 115 ish. Ik it's a jeep but I use to get about 150-175 can't even get close to that. No codes either... Plugs, etc. were done a couple months ago. Any other suggestion before I just burn the thing.
 
#10 ·
Is your speedo accurate? Maybe someone changed out the gear previously
 
#12 ·
I am running 35" MTZ's on mine with horrible 3.07 gearing and if I pay close attention to the RPM's I average 14.8 MPG on the 114 mile trip to and from Washington, DC every day.

I usually try to keep it right about 2000 - 2200 RPM. I know that 2500 is the strong point in the powerband but I have the accelerator pressed deeper to the floor running at 2500 RPM. As long as the gas peddle hits the sweet spot between pressure and acceleration (2000-2200 RPM) I get that magic 14.8.

I know one thing - I will be really happy to swap in my new D44's with 4.88's and get my 4th and 5th gear back.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top