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Re: 2005 Rubicon Gas Mileage

the days of swapping pcm's are over they are v.i.n. specific now

Jeff Hendron wrote:

> I have a 2003 Wrangler Rubicon with the 5 spd, 33x12.50 tires, and ~10,000
> miles on it. I drove it to Moab from Colorado Springs in March and I checked
> the mileage on two tanks of gas. They were both a combination of two lane
> highways, and Interstate 70 driving. The first tank I checked I got 17.6
> mpg, and 17.8 on the second. I was holding it to 65 mph on the interstate.
>
> I don't have a problem with the gas mileage as much as the lack of power. My
> 1991 Wrangler with 4.0L/5sp had a lot more power than my Rubicon! I wonder if
> anyone has tried a non Rubicon ecm in a Rubicon? And would it be as easy as
> unplugging the stock one and plugging in a non Rubicon one or do they interface
> differently?
>
> Jeff Hendron 2003 Jeep Wrangler Rubicon
> MatrixOne Support Skyjacker 4" lift, JKS Disconnects
> Agilent Technologies Fabtech Front Bumper, Rock Krusher Rear Bumper
> Co Springs, Colorado Rock Krusher Rock Rails, Custom Swingout Tire Carrier
> (719) 531-4319 33x12.50 Goodyear MTR's, Mickey Thompson Classic Lock Wheels
> jeff_hendron@agilent.com Bush Whacker Fender Flares, Warn XD9000i Winch
>
> Yamaha WR250ZF
>
> Campbell C Freeman <campbellcfreeman@earthlink.net> wrote:
> : Hello,
>
> : I have a 2005 Rubicon, which I purchased about 2.5 months ago and it
> : currently has 1,800 miles. I noticed shortly after driving it for a few
> : days, that the gas gauge seemed to move to the left rather quickly. I also
> : seemed to be putting gas in it much more often that my 2001 TJ, which I used
> : as a trade. I did the "fill-er-up, same place, same pump, same delivery
> : rate, & cut-off at the pump routine" for a week or two and was amazed to see
> : an average of 10 mpg. The Rubicon (with California Emissions), has an EPA
> : Rating of 15/19, whereas my 2001 TJ had a rating of 16/19. I averaged about
> : 16 mpg with my 2001. Most of my driving is city.
>
> : I did a VIN recall inquiry search on the www.Jeep.com site and found there
> : was an outstanding Emissions Recall - Reprogram PCM: Notification Code D46,
> : for this vehicle. The incorrect version of software was initially &
> : originally programmed into the Powertrain Control Module (PCM), which "could
> : cause the On-Board Diagnostic (OBD) fuel system monitor to malfunction." I
> : called my dealer that day and scheduled an appointment to have the computer
> : reprogrammed. Interestingly enough, that same day I received the exact same
> : recall notice from DaimlerChrysler in the US Mail.
>
> : I took the Rubicon in the next day...reprogramming took about an hour, and
> : off I went. I took a trip out-of-town over the weekend, did some highway
> : driving, and averaged about 17 mpg on 2 tanks of fuel. Three days later I
> : was driving along in town when the Engine Light came on, began flashing, and
> : the motor was running on 5/6 cylinders; skipping horribly. I pulled in to
> : where I was going and called D/C 24 Hour Roadside Assistance. A tow truck
> : was there in under 20 minutes, and off 'she' went to the dealer. Next day
> : I was there when they opened, and stayed to find out what was the matter.
> : The technician told me the computer code said "running lean." He found gas
> : all over the # 6 spark plug and it was fouled. He replaced it but it still
> : ran rough. Next he replaced the injector for that cylinder and that took
> : care of the problem. Off I go, and 'she' is running just fine, but I am
> : still getting 9-10 mpg in the city. This is the 4.0 L I6 w/ a 6 speed
> : manual (the 'new' German transmission), and a 4.11 gear ratio. It is a
> : "stock" Rubicon with everything but the hardtop. To me it runs fine with
> : the exception of this gross gas mileage. Something has to be wrong.
>
> : Even though I do 95% of my driving in the city, I seldom get above 2 grand
> : in either 4th or 5th gear. I am not a "lead-foot." In fact, I "baby the
> : thing" since it is so new. You are in 4th gear at 40 mph with this
> : transmission and rear end. So I usually don't go over 40 in the city, only
> : occasionally getting to 5th on some longer stretches and of course, 6th on
> : the highway.
>
> : What could be causing such terrible gas mileage? I understand that new
> : motors use a little more fuel during break-in, but this is half of the
> : rating (which I realize is not real-world). I am not running the AC at this
> : point in the year yet either.
>
> : Any explanations, suggestions, and/or "fixes" would be greatly appreciated.
> : I will also call the dealership and report the extremely poor mileage.
>
> : Thanks very much,
>
> : Campbell Freeman
> : South Carolina

Re: 2005 Rubicon Gas Mileage

Thanks for the clarification.

JimG

"Jeff Hendron" wrote in message ...
> My speedometer has been recalibrated and is consistent with what
> my gps receiver displays.
>
>
> Jeff Hendron 2003 Jeep Wrangler Rubicon
> MatrixOne Support Skyjacker 4" lift, JKS Disconnects
> Agilent Technologies Fabtech Front Bumper, Rock Krusher Rear Bumper
> Co Springs, Colorado Rock Krusher Rock Rails, Custom Swingout Tire
Carrier
> (719) 531-4319 33x12.50 Goodyear MTR's, Mickey Thompson
Classic Lock Wheels

Re: 2005 Rubicon Gas Mileage

mic,

I believe you are right. I filled up today. 100 miles since last fill-up
and it came out to ~11.75 mpg. That is up ~ 3 mpg in 4 days of driving.
All city driving.

Thanks for the info 'mic canic'.

Campbell C Freeman

"mic canic" <dbrider@cac.net> wrote in message
news:42794E64.FCE8F67D@cac.net...
> the new n.g.c3 computer system takes up to 2000 miles to learn how the
> mange the
> fuel system to optimize fuel milage
> give it a little bit
> "Nathan W. Collier" wrote:
>
>> "Campbell C Freeman" <campbellcfreeman@earthlink.net> wrote in message
>> news:Jhhde.2495$pe3.242@newsread3.news.atl.earthli nk.net...
>> > I have a 2005 Rubicon
>>
>> hi campbell,
>> i also have an '05 rubicon
>> http://7slotgrille.com/jeepers/tj/nathan/index.html and i too am a little
>> concerned about mileage.
>>
>> > I noticed shortly after driving it for a few days, that the gas gauge
>> > seemed to move to the left rather quickly.
>>
>> lol....yes it does.
>>
>> > an average of 10 mpg.
>>
>> you definately have cause for concern. my rubicon is an automatic and im
>> still getting better mileage than you. after several tanks (ive only got
>> 700 miles on it) im getting about 12 mpg. i previously owned two '03
>> rubicons (both with automatics) and they both got 14 mpg.
>>
>> > The Rubicon (with California Emissions), has an EPA Rating of 15/19
>>
>> lol dont pay that sticker any mind. ive never got the rated mileage on
>> any
>> jeep ive ever owned. they either pick those numbers out of a hat or
>> theyre
>> running in a vacuum chamber with no wind resistance. :-)
>>
>> > Something has to be wrong.
>>
>> something is definately wrong. im also a little concerned about my '05
>> and
>> im getting 12. im hoping its just a break-in type issue but i dont
>> remember
>> either of my '03 auto rubis ever getting below 14.
>>
>> --
>> Nathan W. Collier
>> http://7SlotGrille.com
>> http://UtilityOffRoad.com
>

Re: 2005 Rubicon Gas Mileage

Mr. Freeman,
I was wondering if you ever solved your mileage problem? I just bought an
Unlimited Rubicon with the Sahara package last week and am experiencing the
same 10 - 10.5 mpg that you were experiencing. Mine is currently at 800
miles with several tanks of gas. Thank you for any info you may have.

Gerald

--
Right side of the dirt is nice.