so i decided that since my 01 sport 4x4 is almost 10 years old, and has 170k miles, i would start doing some preventative maintenence on it, as time and money allow.
obviously, i keep up on regular oil and filter changes, fix little things as they come up, and i've lately become aware that my gas mileage seems to be not too terribly good.

so i picked up a new throttle position sensor, cheap enough, and i read somewhere on here that a failing or degrading sensor can harm gas mileage.
took just a couple minutes to put on, no problems.

while i was around the throttle body, i decided to put a socket and ratchet on the tb mounting bolts and make sure it was tight....well i'm glad i did, because they needed to be torqued down!!!

i had been averaging between 13-16 mpg around town/rural roads...i don't do much freeway driving.
just filled up the tank for the first time since installing the new tps and tightening down the tb.(filled up just after working on it...)
19.3 mpg!!!!!!

needless to say i'm stoked!

going to keep replacing things as i can afford to, my xj unfortunately has 4 o2 sensors, so it may be awhile....i figure cps will be next.

just thought that someone could possibly get some use out of this...

 

run a full tank through and then post up your mileage

 

thats what i did....started with a full tank and trip odometer at 0...drove until my gas light came on, filled up and divided miles driven by gallons of gas used to fill up tank. been doing this awhile so i can monitor changes in mpg.

by the way, i do tend to drive like a grandma....


edit: ok, gotcha...post total # of miles driven/tank of fuel....its late and i misread!

 

16.8 gallons took me 324.2 miles =19.29 mpg.

 

What size tire are you running? Do you have stock gears?

 

Don't forget about cooling system maintenance for your 01 as it has the "infamous" 0331 cylinder head, which is very prone to cracking upon an engine overheat.

Get those hoses replaced if they are original, there are only 4 hoses if I remember right. A new radiator cap will set you back all of $5.00

Keep up with coolant flushes and a new 195 degree stat once in a while.

 

i am running 30x9.5 on stock gears. when i first got the tires installed, i was curious as to whether the speedo would be off, so i grabbed the wifes gps and went for a drive....throughout the entire drive 25mph up to about 75mph, the needle on the speedo was dead on to what the gps was saying speed wise. it appears that my xj with stock speedo gears is calibrated darn near perfect with rolling 30" tires!!! i was worried that i would have to do on-the-fly calculations.

as for the cooling system, that is on the list of things to do... i have had no issues thus far with the temp gauge reading anything fishy, the needle is generally vertical, with very minute variance of the needle when sitting in traffic or driving.
fluid in the radiator is topped off, and the overflow tank is also at the proper level.

i believe that there has been some work done to this jeep before i bought it, but unfortunately i have no way of knowing exactly what. it was driven by a woman, whos father apparently did religious maintenence....but without seeing it done, i naturally assume that if i haven't done it, then it hasn't been done.

 

veering off topic

Is the temp gauge you have the stock one or a aftermarket? Most stock gauges, temp or otherwise wont move very much if at all. They're generally not a gauge of temp as much as a gauge of whether things are working or not. Cant have the masses seeing a shift and bringing the car in to the shop.

Otherwise its interesting you found that much extra mileage. Hopefully it sticks around.

 

Was there something other then the forum posts that indicated replacing the TPS? Such as poor acceleration, rough idle, smoke out the tail pipe, etc.

Did you test the TPS prior to replacing it? Is there an adequate test for the TPS?

Any additives in the tank? Any cleaning of the throttle body? Recent oil change?

What about roof rack, accessory lights, anything that would increase/reduce wind resistance?


My 2001 with 3" lift, 30x9.5x15 Treadwright tires, Rock-it Intake, DynoMax Super Turbo Cat Back Kit, and 162k miles gets 15-16mpg. 19-20 that I see on here would be a nice result. I figured people with 20+ mpg were running 4 cylinder engines, stock tires, and no lift.

 

I can't figgure out how some people are getting such good millage....my stock 2000 with 4.0 and new neon injectors gets 14.

 

You should be able to pull 16-21 mpg on your 2000, depending on how you drive it, the state of engine efficiency, and the outside temperature.

I'd start testing some of your engine management sensors.

Coolant temp sensor, map sensor, oxygen sensors for starters. If you have 100k plus on your oxygen sensors, as they are tough to test for the average do-it-yourselfer, just replace them. Especially the upstream one as the input from that one is involved in calculating fuel/air mixture.

 

My stock XJ with a front bumper(about 60 lbs) did just under 20mpg.

 

This has a lot to do with mileage as well...

My 93 XJ (stock, 235s, 5speed, 4.0) gets about 20-21mpgs.. and I haven't tuned it up since I got it...3 years ago. I keep the RPMs low, coast when possible, and ease up to speed.

 

170,000 miles...new - head, up stream O2, map sensor, intake temp sensor, temp sensor, belts, hoses, plugs, boots and springs, egr fittings and air filter.

I have driven it easy and 14 is the best I've got.

 

Your gas mileage makes me want to cry lol... I get an average of 110-130 miles to 18 gallons of Shell gas. Sadly, Shell lasts the longest in my rig, lol.


What makes my horrible gas mileage hurt even worse??? It's my daily driver


Time for a....