WHOOPS!
Excuse my last post....

It consumes 1/8 tank per round trip (34miles est.)
20 Gallon tank

so something like 272 mpt (miles per tank)

I have bad city mpg's and even worse on the highway...I do best between 35-50MPH with 31's...I have no clue what its gonna be with these 33's

How are you figuring this stuff out???

I Would really like to know! Its interesting to me.

mine comes on at 200 and off at 185. seems great

88 laredo...340.000+...(still gets good oil press, and doesn't smoke/consume excess oil)
terrible gas mileage!
32's 4.5" lift...steel cragers...but
the funny thing is, it started getting bad mil before I put the lift/tires on, then that just made it worse......
12-15 around town/dd driving. maybe 16-17 on freeway if I'm lucky......
speedo seems to be off by 3mph (if I'm doing 50, its really 53)
Oh and it has 307's in the pumpkins.....ugh.
410's would prolly help, but no Cheddar....
Any advice?
Anybody?

yeah. run 235/75/15s on the road and your 32s when you wheel. I think you getting pretty good milage for a that much loved motor. Those have o2 sensors? if so change it and whatch what happens

Been there, done that, new O2 sens, adjusted TPS, replaced IACV, replaced coolant temp sens, (not the sender, the one down low on the block)
cleaned TB, K&N air filter (kept clean of course)
Checked for vac leaks,
Nothing seems to help.
I should try replacing the TPS, and see if that helps.
Maybe the MAP sens?
The motor is still pretty spry for its mileage, but I realize that its past its prime.
I should be getting at least better mileage than a souped-up push-rod V8!
Knock sens is cracked, would that do it? I had replaced the IACV because of the "high rev" issue that lots of ppl have had on this board, but it still does that occasionally as well! (new Idle Air Control Valve wast of money...lol)
I'm tired of throwing green at it....

so dont throw any more money at it. drive her r till she dies. but when hover cars start passing ya on the highway go a head and retire her

Roflmao! thanks
here's link to an old post I did on this trouble....
https://www.cherokeeforum.com/f2/guzzler-27586/
This is all me and my family have to drive, I want an economy car but cant afford another vehicle
Sign of the times eh?

I was just using the numbers that posjeepxj posted. Here are the conversions: A stock tire on an XJ (factory) is 215/75/15, which is, 215mm width / 75% side wall / 15" wheel dia. That all comes out to about 27.7" overall dia for a stock tire. He said, on stock tires, he gets 240 mi per tank.
On 31" tires, he gets 210 mi / tank. Now, the speedo errs 11.9% on larger (31") tires, but his fuel consumption is 30 mi less, which is 1/8 (12.5%). So, pretty close. But on 33" tires, the speedo errs 19.13%, means, if your odo says, it's gone 100 mi, the car really went 119.13 mi. So, he said, he got 170 mi on 33s, which is 70 mi less than on factory (27.7"), which is 29.16% less. And, this is 10.03% more than the speedo error with 33s. So, I don't know the exact mpg he gets, but if I assume the 20 gal tank, it's about 12 mpg with factory tires, 11.93 mpg with 31s, and about 10.8 mpg with 33s, all provided, the tank was completely full.... But, he said, that after changing to an electric fan, he got 185 mi on 33s. Haha, to make matters worse... he got increased gas mileage with the elec. fan by 8.82% on 33s (or, lost 3.78% over the stock setup), which comes out to 11.55 mpg.

Dude, 340k miles... I remember a thread on here discussing the reliability of an XJ. You should've been there

by tank i mean when gas light comes on. When i fill up i average putting in 15.2 gallon

Then it's 15.8 mpg with the stock setup, everything else is just a percentage. That's really not bad. I get 23 to 24 mpg, BUT: My overall driving is 75% freeway, I try to implement gas-saving techniques most of the time (speed limit, shift @ 2k rpm, avoid braking as much as I can, keep the go-pedal steady, etc.), I have a 4-banger with the AX5. I'm happy with that, it could be much worse.

My goal is to get 20mpg average when it all said and done. but im guna dump in a a fresher motor (4.5). O yeah, i drive like an a-hole %80 of the time, to the wood

year: '92
mileage: 166,000
tire size: 30x9.5 on aluminum wheels
driving style: Moderate acceleration to speed limit.
aftermarket: 3.5" lift.
city/highway ratio: 17/24

Helps that I'm 2wd with ax-15.

Hey guys, I see some of us share the same problem. Terrible mileage with no cause. I've put so much time and money into this it hasn't been funny for months.

Has anyone changed out the MAP sensor? I am going to check the Fuel injectors and the map sensor. After that, I can't say what I'll do.

The IAT sensor is a waste too.