Horrible MPG unsure why
#1
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Year: 1998
Model: Cherokee
Engine: 4.0
Horrible MPG unsure why
i have a 1998 cherokee with the 4.0, and i just did a 154 miles on a 19gallon tank which comes out to 8.1mpg. its lifted 6.5 inches and on 35's and not regeared, in no way am i expecting high teens but the high single digit doesnt seem quite right. curious to see if anyone else has had this same problem and if so how you went about fixing it, or any ideas on how my mpg is so low?
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Year: 1987
Model: Cherokee
Engine: 4.0
i have a 1998 cherokee with the 4.0, and i just did a 154 miles on a 19gallon tank which comes out to 8.1mpg. its lifted 6.5 inches and on 35's and not regeared, in no way am i expecting high teens but the high single digit doesnt seem quite right. curious to see if anyone else has had this same problem and if so how you went about fixing it, or any ideas on how my mpg is so low?
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Year: 1997
Model: Cherokee
Engine: 4.0
Are you calculating the fact that less miles show on odometer to how many you actually went with 35s over stock size? On my 33s if I went 200 miles, it actually came out to 220 miles. To a full tank I get around 180-190 on the odometer which is around 190-205 actual miles.
You can't expect much running stock gears, on a high lift, with that size of tires. Honestly I would consider getting 10mpg great mileage on 35s and stock gears.
You can't expect much running stock gears, on a high lift, with that size of tires. Honestly I would consider getting 10mpg great mileage on 35s and stock gears.
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Year: 1990
Model: Cherokee
Engine: 4.0
I average about 15 mpg on 35s, 3.73 gears and a 5 speed. One HUGE thing you need to do is get your Speedo gear replaced, so you aren't speeding and your mileage on the odo rings truer
#7
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Year: 1998
Model: Cherokee
Engine: 4.0
thanks for the help
On the one tank of gas ot was mainly in town with one off roading trip so I could see how that woukd drop my mpg. My Speedo is off by about 12mph, I didn't even think about the fact that I'm going farther then it says. Thanks for all the help, I'm new to the cherokee world but I absolutley love it.
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#8
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Year: 1999
Model: Cherokee(XJ)
Engine: 4.0
On the one tank of gas ot was mainly in town with one off roading trip so I could see how that woukd drop my mpg. My Speedo is off by about 12mph, I didn't even think about the fact that I'm going farther then it says. Thanks for all the help, I'm new to the cherokee world but I absolutley love it.
#10
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Year: 1999
Model: Cherokee
Engine: 4.0 I6
You're lucky to even get that.
I'm running 33's with 4.56's and I still only get around 10 MPG in city. That's with 784 injectors and complete tune up.
I'm running 33's with 4.56's and I still only get around 10 MPG in city. That's with 784 injectors and complete tune up.
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Year: 1987
Model: Cherokee
Engine: 4.0L
Differently regear anyways besides the bad gas mileage, so much more fun to drive correctly geared.
I would look at TPS, MAP, O2 sensors, spark plugs and cleaning your fuel injecters for starters. Maybe check out your fuel filter and pump too.
Definitely check your exhaust and see if it is rich like what Mr White suggested to see if it is super rich or not.
Also make sure your air filter is clean, that makes a bigger difference than you think and often gets forgotten about.
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Year: 90,84
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Engine: 4.0,2.5
If it were 4%, 100 miles on the odometer would really be 104 miles. If the speedo said 50, you'd really going 52. 25 would really be 26, 75 is 78, ect...
(on a calculator, you might just punch +....4....%)(to add the 4% to your miles, before you divide by Gals.)
THEN one tank isn't really much of a test. Any little angle filling up, different pumps....Gotta go at least a couple of tanks and keep accurate numbers to get a meaningful MPG figure.
4% was just a random example.
#13
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Year: 1999
Model: Cherokee
Engine: 4.0 I6
I have the same setup and get 16 MPG highway and 12-13 MPG city and am just thankful for that.
Differently regear anyways besides the bad gas mileage, so much more fun to drive correctly geared.
I would look at TPS, MAP, O2 sensors, spark plugs and cleaning your fuel injecters for starters. Maybe check out your fuel filter and pump too.
Definitely check your exhaust and see if it is rich like what Mr White suggested to see if it is super rich or not.
Also make sure your air filter is clean, that makes a bigger difference than you think and often gets forgotten about.
Differently regear anyways besides the bad gas mileage, so much more fun to drive correctly geared.
I would look at TPS, MAP, O2 sensors, spark plugs and cleaning your fuel injecters for starters. Maybe check out your fuel filter and pump too.
Definitely check your exhaust and see if it is rich like what Mr White suggested to see if it is super rich or not.
Also make sure your air filter is clean, that makes a bigger difference than you think and often gets forgotten about.
Never replaced the TPS/fuel pump but I've never had a CEL for anything like that or any problems related to them.
#14
I have the same setup and get 16 MPG highway and 12-13 MPG city and am just thankful for that.
Differently regear anyways besides the bad gas mileage, so much more fun to drive correctly geared.
I would look at TPS, MAP, O2 sensors, spark plugs and cleaning your fuel injecters for starters. Maybe check out your fuel filter and pump too.
Definitely check your exhaust and see if it is rich like what Mr White suggested to see if it is super rich or not.
Also make sure your air filter is clean, that makes a bigger difference than you think and often gets forgotten about.
Differently regear anyways besides the bad gas mileage, so much more fun to drive correctly geared.
I would look at TPS, MAP, O2 sensors, spark plugs and cleaning your fuel injecters for starters. Maybe check out your fuel filter and pump too.
Definitely check your exhaust and see if it is rich like what Mr White suggested to see if it is super rich or not.
Also make sure your air filter is clean, that makes a bigger difference than you think and often gets forgotten about.
4.56 gears, 35's, automatic. Calibrated the speedo to within 3% (which was better than stock at 10% low). Confirmed by GPS and roadside radar markers.
I only see 8mpg on the trail in 4lo.
The stock gearing is way too low for 35s, you have to dig your foot deep to go anywhere, meaning ... Bye bye gas mileage (not that a Jeep ever had decent economy to start).
My solution, get the damn MJ back on the road so I can stop daily driving my trail rig. It was never built to roll the highway.
Last edited by Rockfrog; 10-02-2014 at 11:22 AM.