Consuming to much fuel?

RoboG

RoboG

Member
Joined
Apr 2, 2018
Messages
57
Location
Athens, Greece
Hi TJ friends,
I realized recently that my jeep is consuming gasoline the same way I consume food. The latest metrics is 23lt/100km for a 2.4cc 2005 TJ, which is a lot. No engine sign or any feedback from the car. Yes Im wearing bigger tires 31/10.5/15 but this can't be the difference. Any thoughts?

no boundaries no borders - wrangler
 
How is s running? Any codes? When was it tuned up last? The 2.4 gets ok mileage but it isn't like a commuter car. I get around 19 on hwy and 16 around town which is about the factory standard. I run 31's with 4.88's.
 
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I get 13 mpg with 35x12.5 and 4.88 gears (nv3550) I also got 13mpg with 33x10.5 and 4.10. I'm reducing my driving speed by 5mph this tank to see what effect it has on mileage.
 
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I am not familiar with Greece, but last December I put a lift on my Jeep, and it was down for a couple of weeks on some other unrelated reasons. After I started driving it again I noticed quite a few(lot more miles on a tank of gas and I thought surely a lift kit didn't net me better mileage. After taking a minute to think about it I remember the weather got better and I wasn't running my air conditioning.

I am not sure what it is like where you are, but are you doing anything differently, like running A/C or driving like a race car driver? Any change in habits?
 
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I am about 11 mpg with my 4.0 2002 auto 32rh... I have 33'' wheels and 3.07 gear...
Do you think that is normal ?
May be it can be a problem of plug spark? Because I just discovered that I run with the bad plug spark...
Thank s
 
Medali said:
I am about 11 mpg with my 4.0 2002 auto 32rh... I have 33'' wheels and 3.07 gear...
Do you think that is normal ?
May be it can be a problem of plug spark? Because I just discovered that I run with the bad plug spark...
Thank s
Click to expand...
fix the misfire and get it geared properly and you should see a few more MPG's.
 
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I will try . Thank you
I am hesitating between autolite double platinum and autolite iridium... Especially because there is not a big price difference between the two...
 
Medali said:
I am about 11 mpg with my 4.0 2002 auto 32rh... I have 33'' wheels and 3.07 gear...
Do you think that is normal ?/
Click to expand...
You're undergeared for 33's with 3.07 and your engine is lugging. Regear your axles to 4.10 to get the engine RPM's back up where they should be and your engine will run far more efficiently. Lower rpms don't always mean better mpg. I raised my engine RPM's by regearing from 4.88 to 5.38 for my 35's with the 42RLE automatic transmission and my mpg went up to over 14 mpg from never over 12 mpg.
 
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Jerry Bransford said:
You're undergeared for 33's with 3.07 and your engine is lugging. Regear your axles to 4.10 to get the engine RPM's back up where they should be and your engine will run far more efficiently. Lower rpms don't always mean better mpg. I raised my engine RPM's by regearing from 4.88 to 5.38 for my 35's with the 42RLE automatic transmission and my mpg went up to over 14 mpg from never over 12 mpg.
Click to expand...
What RPMs are you turning now?
 
does keeping my current configuration momentary (33 "wheels with 3.07 gear) and only changing the speedometer gear (30 to 26 teeth) will reduce my problem a little bit ...? knowing that I have an automatic gearbox (32rh) ...
Thank you
 
dimension12 said:
Was thinking of going to 4.56 from 3.73 with my 32RH and 33s.
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I'd advise 4.10 for 33's with your 32RH if you drive your TJ on the highway much. Your rpms would be just over 3000 at 65 mph with 4.56 and 33" tires. With 4.10 you'd have a more reasonable 2695 rpms at 65 mph.
 
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Jerry Bransford said:
I'd advise 4.10 for 33's with your 32RH if you drive your TJ on the highway much. Your rpms would be just over 3000 at 65 mph with 4.56 and 33" tires. With 4.10 you'd have a more reasonable 2695 rpms at 65 mph.
Click to expand...
My ECU got water in it from a car wash. Plugged a reflashed reman one in and plugged my TCC solenoid back in and it now works properly. Checking my mileage next week. The old ECU must’ve had multiple problems. The old girl runs so much better. Also thought 4.10 was the proper way to go for a daily driver after finding out your RPMs.
 
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