Poor Gas Mileage

[juliad]

Hi Folks,
I have a 1995 Jeep Grand Cherokee that I bought about 5 months ago. The mileage has gradually deteriorated to about 8 mpg in the city and 24 mpg on the highway. I had the oil and oil filter changed and the mileage went up to 13 mpg/city and 29 mpg/highway (which i could live with--not thrilled of course) However, 2 days later I filled up the tank and took a 100 mile trip. My mpg is now down to 22 on the highway. I went to a discount gas station last time I filled up. Could that be part of the problem?

Also, the car is idling roughly. Could anyone tell me all the things I need to do to this car to get optimum mileage from it? I have all the work records on this car (which was cared for beautifully) so I can check when anything had been done to it. It has 118,000 on it.

Thanks very much. Julia

[william moore]

Hi
ABOUT 22 HIGHWAY IS GOOD HAVE A 97 GC i6 AND THATS THE BEST I CAN GET

[mycivic]

dont know for the city driving. but my uncles grand cherokee goes like 18-20 mpg i guess. i think he has the limited edition which is the V8. i hope this info helps. dont know about the V6 though.

[Bronco2]

Some thoughts-gas milage goes down in colder weather and driving habits-8 mpg city is wrong-do you have the correct thermostat installed-the O2 sensor could be weak-the coolant temp sensor could be off scale and sending the wrong temp to the ECM-has the truck had a set of plugs and wires?Is the air filter plugged up? Have you checked your tire pressure lately? Hope this helps.

[richpinkham]

I have a 99 Grand limited with the I6 and it usually gets around 22 mpg also so if you got 29 then you must have had just perfect conditions and very good gas. Wish they all got that kind of mileage

[jWiles]

Sounds like you should probably check your fuel filter and air filter. Clogged filters can cause rough idling and bad gas mileage. Good Luck. By the way I'm new here, so Hi everybody.

[JackGivens]

I have a 98 Ltd Grand Cherokee V8. I get about 11mpg city and 17mpg on the highway. Does this sound right to everyone?

[rr504]

I have a 2001 Gran and I put a K&N air filter into it, which gave me better mileage all around. The cost of the filter should be covered over the life of the vehicle.

[Griffon327]

Originally Posted by juliad

Hi Folks,
I have a 1995 Jeep Grand Cherokee that I bought about 5 months ago. The mileage has gradually deteriorated to about 8 mpg in the city and 24 mpg on the highway. I had the oil and oil filter changed and the mileage went up to 13 mpg/city and 29 mpg/highway (which i could live with--not thrilled of course) However, 2 days later I filled up the tank and took a 100 mile trip. My mpg is now down to 22 on the highway. I went to a discount gas station last time I filled up. Could that be part of the problem?

Also, the car is idling roughly. Could anyone tell me all the things I need to do to this car to get optimum mileage from it? I have all the work records on this car (which was cared for beautifully) so I can check when anything had been done to it. It has 118,000 on it.

Thanks very much. Julia

I have a 1998 Limited with AWD and 5.2L V8 and average 14.6 mpg around town and have a lead foot. when I drive it more conservatively it gets around 16-17 mpg around town. I would just love to have your gas mileage. If you had a major change in your fuel economy on your trip I would look at the gas ( grade and where purchased) and did you sleep during the trip with a friend driving? if he was bragging about how long it took to him to get there then he most likely has a lead foot also. I just love picking on the little import 4 bangers with there fart pipes and car load of teenagers at the redlights as a AWD V8 Grand cherokee with 4.11 gears takes off like a rocket and always leaves them in the dust.