8 MPG! WHY?
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8 MPG! WHY?
I have an 89 Cherokee Laredo that gets 8 MPG in the city. So far I have replaced the plugs, o2 sensor, fuel filter, air filter and vacuum harness. I checked my tire pressure and it is fine. It idles around 1000 RPMs and bounces around a tiny bit. Seems to be a lot more effiecient on the highway. I am starting to think it is just an old Jeep and this is the best it can do. Any ideas?
#3
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
This is NOT normal.
Cap, rotor and wires are due to be changed with the plugs.
Intake manifold bolts loose?
Line to the MAP sensor or fuel pressure regulator leaking?
Go to www.cruiser54.com and do Tips 1,3,4, and 5 soon.
Cap, rotor and wires are due to be changed with the plugs.
Intake manifold bolts loose?
Line to the MAP sensor or fuel pressure regulator leaking?
Go to www.cruiser54.com and do Tips 1,3,4, and 5 soon.
#4
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Year: 1990
Model: Cherokee
Engine: 4.0
My 90 w/ 4.0, auto, 4.10 gears and 33s gets 13.2 mpg currently. Mine is running rich, you can smell it at idle. I can only IMAGINE what your's smells like, must burn your eyes! Definitely not normal.
#5
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I calculate my miles by setting my odometer to zero when I fill up and dividing that by the gallons it takes to fill up next time.
I will do those tips as soon as I get back from a trip I am leaving on tomorrow. By lines to the MAP sensor are you talking about electrical wiring to the sensor.
I am taking it to the coast tomorrow so I will calculate the MPG on the highway
I will do those tips as soon as I get back from a trip I am leaving on tomorrow. By lines to the MAP sensor are you talking about electrical wiring to the sensor.
I am taking it to the coast tomorrow so I will calculate the MPG on the highway
#6
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
vacuum line from the throttle body to MAP and vacuum line to fuel pressure regulator. If they're not perfect bad fuel mileage will be a result.
#7
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Vacuum lines are in good condition. Could it be the MAP sensor itself causing such a problem? The weird thing is it gets 15 MPG on the highway and only 8 in the city.
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#8
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Year: 1998 Classic (I'll get it running soon....) and 02 Grand
Model: Cherokee (XJ)
Engine: 4.0
Wow!
We have 7 posts on a "sub-10MPG" thread and so far nobody is trying to tell him to drive more carefully or it's his big tires!
Nice!
We have 7 posts on a "sub-10MPG" thread and so far nobody is trying to tell him to drive more carefully or it's his big tires!
Nice!
#11
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
#13
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Year: 1990
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#14
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Year: 1996
Model: Cherokee
Engine: 4.0L
Probably stretched timing chain/bad guides, timing is off due to this.
My Cherokee got 21.8 mpg at 65 mpg with all terrains, 1,000 pounds of people and 200 pounds of stuff in the trunk. This was after having the timing chain replaced and the distributor.
My Cherokee got 21.8 mpg at 65 mpg with all terrains, 1,000 pounds of people and 200 pounds of stuff in the trunk. This was after having the timing chain replaced and the distributor.