BAD GAS MILAGE

So what have you already tried ?

Dave Milne, Scotland '91 Grand Wagoneer, '99 TJ

Are the brakes dragging? I had that happen once...

Let's face it. That engine has seen better days and is very inefficient. (It's being dumped by Chrysler.) My I-6 Wrangler, which is a few hundred pounds lighter than your Cherokee, does well to average 14-15 mpg. And my Dodge Magnum RT (Hemi V-8) averages 19-21!!!

Plugged air filter or maybe a dead O2 sensor for a couple guesses.

When was the last time you changed the distributor cap, rotor, wires and plugs? All of those have effect.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >

My 95 (owned since last October) gets about 13 mpg if I try, and about

11 mpg if I leadfoot it :( Although, on ONE tank, where I tried to use as much of the tank as possible, I actually got 15 mpg!! (And I still only had to put 18 gal. back into it!?!)

...

Well, having the aerodynamics of a brick doesn't exactly help the XJ anyway...

Shift UP! ;)

Mike Romain did pass the time by typing:

The O2 sensor will definitly knock 2-3 mpg off. So will a clogged filter.

..and a leaky fuel line.. :]

I also wonder what tires your running. Stock or lifted with larger wheels.

Leaky vacuum lines can also cause your engine to run a bit higher RPM at idle. Not sure if it changes milage by that much though, usually just makes things a bit rough.

I'm getting about 14-15 but then again my 4.0 is slightly modified.

And my `96 Cherokee 4.0L usually gets 20 MPG highway, the same mileage as my `89 Cherokee 4.0L got. Running in Full-time 4WD reduces it a bit.

Among other useful things that "pond jumper" might do is to sniff near the left rear wheel for gas fumes. If he smells any at all he should check his long-neglected fuel filter for rust-through and leaks.

Jack Carter wrote:

The reason for it's discontinuation has nothing to do with efficiency, or suitability to purpose. The I6 is the consummate Jeep engine for long reliable life with high torque at low speeds. It's all about materials and machining. The I6 weighs in at almost double that of today's current production V6's. In addition, production machinery wears out. The large transfer line machining systems that produce the I6 are at their end of life. It is cheaper to just grab some current production piece of DC crap and slap it in.

There's something wrong there. You should be getting better than that.

Worse, you're wasting your money. If you drive 15,000 miles/year at 13 MPG you're burning about 1,154 gal. a year. At 20 MPG you're burning

750 gal. At $2.40 (roughly the current national average) that's a $970 annual difference. Put it another way, that's nearly $20 a week falling out of your pocket.

Other fixes aside, religiously check your tire pressure -- it _does_ make a difference and you can't tell by eyeballing a radial -- and carefully track your tank-to-tank mileage, noting which station you buy at. A pain in the ass? Perhaps, but it will cost you all of two minutes every time you fill up. You /might/ find that a particular brand of gas gives better mileage than another, and even enough to offset the price difference. Yes, pretty much all of the gasoline base comes out of the same tap, but what the seller adds to it may make a difference in your mileage.

I'll say!

We would have dumped our Jeeps years ago if that is all the mileage we could get.

I get a nice 23 mpg in my old CJ7 and way better than that in our Cherokee. The 'worst' we ever got on the highway in our Cherokee had 4 adults and winter camping gear to the roof inside with 3 duffel bags on the roof rack. We 'only' got 23 mpg on that trip.

The Cherokee does really short trips in the city, not enough to warm up or fully defrost the windows before being shut down and it only gets 14 mpg driving like that. 24-26 mpg on the highway makes for about an 18 or 19 'combined' mpg.

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 (More Off Road album links at bottom of the view page)

I do very little "highway" driving. It's almost all "city". And it's veeery easy to lead foot around town ;-) My tire pressure might be a bit low, so I'll see how much that helps. And I usually use Shell gas, but sometimes I use Chevron or an independent in a pinch. I have no idea what gas brand I used for the tank that got the 15 mpg though. I also want to change out the axle and transfer case fluids since I have no idea if the previous owner(s) ever did it.

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Get a front end alignment or at least get it checked.

What year Wrangler? TJ's are actually heavier than XJ's in stock form....

"Matt Macchiarolo" wrote in news: snipped-for-privacy@comcast.com:

Our two 97TJ's with 2.5's and 5 speeds, soft top, 30x9.50's with the correct spedo get 20-21 local, 22 hiway, downside is having to use 3rd uphill on the interstates. Our 93YJ 2.5 gets 20 around town, hard top 5speed. My 98XJ 4.0L 5speed, LT235 BFG AT/KO's gets 21-23 in my morning 32 mile commute from the poconos to allentown pa on the turnpike at 80mph, 2200rpm 5th gear, reverse in the evening.... it needs a tune up, skipped it last year and it shows, used to get 24mpg. Mobil-1 engine oil, Mobil-1 atf in TC, Mobil-1 Gear oil in AX15 and front diff, drydene in the rear with it's auburn LSD...I also run my tires at 40lbs.