Fuel economy - bad to worse

Hi, my 01 TJ (4.0L Auto) seems to have lost whatever fuel economy it had
before. Lately, I can only do about 300kms on a full tank. I am
running 265/70R16s and an OME lift. These mods did not change the fuel
economy when they were done two years ago. Could it be that the O2
sensor has gone bad? There are no error codes or check light coming up.
Every thing else feels/runs fine. Any ideas?

Thanks
TW

Billy,

Tyre pressure checked every week (running at 30psi), air filter replaced
Dec '05, spark plugs replace d Dec '04, front brake pads replaced two
weeks ago, diff oil changed Dec '05, ATF changed Dec '05. Any other ideas?

Thanks
TW

billy ray wrote:

> Tire pressure, air filter, spark plugs, dragging brakes, diff lube, ATF...to
> start..
>
>
> "TW" > wrote in message
> ...
>> Hi, my 01 TJ (4.0L Auto) seems to have lost whatever fuel economy it had
>> before. Lately, I can only do about 300kms on a full tank. I am running
>> 265/70R16s and an OME lift. These mods did not change the fuel economy
>> when they were done two years ago. Could it be that the O2 sensor has
>> gone bad? There are no error codes or check light coming up. Every thing
>> else feels/runs fine. Any ideas?
>>
>> Thanks
>> TW
>
>

I don't know what your octane ratings are in New Zealand, but as
our oil companies have had to take a lower grade of crude at seventy
seven bucks a forty four gallon barrel, the bounce to the ounce has
suffered. Also, here we have tried to save money by switching from a
major suppliers of gasoline to something with alcohol in it, knocking
off about twenty percent in economy and power.
God Bless America, Bill O|||||||O
http://www.billhughes.com/

TW wrote:
>
> Hi, my 01 TJ (4.0L Auto) seems to have lost whatever fuel economy it had
> before. Lately, I can only do about 300kms on a full tank. I am
> running 265/70R16s and an OME lift. These mods did not change the fuel
> economy when they were done two years ago. Could it be that the O2
> sensor has gone bad? There are no error codes or check light coming up.
> Every thing else feels/runs fine. Any ideas?
>
> Thanks
> TW

TW wrote:
> Hi, my 01 TJ (4.0L Auto) seems to have lost whatever fuel economy it
> had before. Lately, I can only do about 300kms on a full tank. I am
> running 265/70R16s and an OME lift. These mods did not change the
> fuel economy when they were done two years ago. Could it be that the
> O2 sensor has gone bad? There are no error codes or check light
> coming up. Every thing else feels/runs fine. Any ideas?

O2 sensor drift can cause lower milage. I have noticed that as well.
The problem is the drift is so slight it's hard to tell without being
anal with the records.

For example. http://www.revbeergoggles.com/gasminder/

The pdf is just a chart of date/mpg and date/fuel cost.

the spreadsheet has all sorts of stuff in it. Need to update a few
things.


--
DougW

Tune up time?

Lots of folks forget about the distributor cap and rotor....

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

TW wrote:
>
> Hi, my 01 TJ (4.0L Auto) seems to have lost whatever fuel economy it had
> before. Lately, I can only do about 300kms on a full tank. I am
> running 265/70R16s and an OME lift. These mods did not change the fuel
> economy when they were done two years ago. Could it be that the O2
> sensor has gone bad? There are no error codes or check light coming up.
> Every thing else feels/runs fine. Any ideas?
>
> Thanks
> TW

It could be the recent change in the fuel formulas.
Don't know if you are running the same thing we are here in the states, but
the new fuels decrease your mileage and sometimes as much as 5mpg like it
did in our Liberty.

Kate

"TW" > wrote in message
...
: Hi, my 01 TJ (4.0L Auto) seems to have lost whatever fuel economy it had
: before. Lately, I can only do about 300kms on a full tank. I am
: running 265/70R16s and an OME lift. These mods did not change the fuel
: economy when they were done two years ago. Could it be that the O2
: sensor has gone bad? There are no error codes or check light coming up.
: Every thing else feels/runs fine. Any ideas?
:
: Thanks
: TW

Mike Romain wrote:
> Tune up time?
>
> Lots of folks forget about the distributor cap and rotor....

An 01 TJ is distributorless there oh great "technician"

--
Simon
"I may be wrong, but I'm not uncertain." -- Robert A. Heinlein

Simon Juncal wrote:
>
> Mike Romain wrote:
> > Tune up time?
> >
> > Lots of folks forget about the distributor cap and rotor....
>
> An 01 TJ is distributorless there oh great "technician"
>
That's right, losers always come out with the insults. Calling me a
'technician' now, ouch that hurts....

Mike

Mike Romain wrote:
> That's right, losers always come out with the insults. Calling me a
> 'technician' now, ouch that hurts....

What in the world are you saying here?... On the first score, you
started with the insulting in the other thread, on the second sco do
you not understand what sarcasm is?

You're a great help to a lot of people here over the years, I've nothing
against you personally except for the kooky fact that you think the
Carter BBD is better then anything created after it, inlcuding fuel
injection and several other much better working Carbs, like the popular
motorcraft and weber 2bbl swaps.

--
Simon
"I may be wrong, but I'm not uncertain." -- Robert A. Heinlein

Simon,
Ninety percent of the advice I write is for the group as a whole.
We talking about a car with a hundred thousand miles on it, that's
probably been neglected, meaning the spark plugs have over the
recommended thirty thousand miles. And mike was reminding these people
using a search engine to trouble shoot their failing engines, to include
ignition wires, cap, and rotor that are often forgotten.
God Bless America, Bill O|||||||O
http://www.billhughes.com/

Simon Juncal wrote:
>
> An 01 TJ is distributorless there oh great "technician"
>
> --
> Simon