Dear friends, my wife's KJ is has 80k miles on its odometer. it is awell maintained car with no known problems. i am maintaining it and important and relatively dirty maintenance are done by chrysler dealer in my city. i have a nice conneciton with them and most of things are done according to fsm.

can has no problems during normal operation. no viration, no stalling, no o2 sensor problems ( as far as a observe), TPS and crank position sensors has been replaced when we bought this car 3 years ago. Spark plugs are not bad, intake valve is not that dirty etc. i replaced its ATF with proper mopar stuff last year. tires are stock. everything is stock.

car has bifuel setup, so it can operate on gasoline or LPG. our problem is always there regardless of fuel type.

when travelling slow, when i want to kick it hard, it reluctantly kicks down, when it kick, kick down feeling is no harsh as well. it shifts early and always try to shift up and stay there. acceleration before 3900 rps is slow. slooooower than i remember. ( i am driving 3.0 CRD WK for 1year and forgot how this KJ feels) when it reaches to 4000 rpm, it starts to accelerate faster until it red lines. there is no fuel supply problem. it is same on LPG setup. feeling oafter 3900 rpm is , somebody has jsut started to push from back. or it feels like a turbo lag at low rpms on small engine equipped passenger cars sold in europe.

can this be a slipping transmiison on lower rpms? or related to torque converter? may be it is not locking until it reaches a certain rpm?

 

update. i drove it this morning. it works as intended. no hesitation. it accelerates continuously at same increasing speed. variables changed from evening are:

outside temperature, ofcourse engine oil and transmission oil temperature.

any comments?

i tried antoher thing, i treid to climb on a rough surface, slope was not that serious, i hold gas pedal at a certain position, it kicked down and shifted up, kicked doown shifted up. it cant monitor current cruising speed/transmission speed i guess.

 

i started to feel idling problems. intermitten rough idling is there also when cold, when approaching to red light, i hear it tries to increase rpms a little and decides no to.

exact sympotoms i face when i had a broken TPS 2 years ago.

 

i replaced TPS with a new one. it didnt cure.

what next?

 

update. weather is colder. car is responding much better. it is fast.

it seems those problems are all related to ATF temperature.

 

Hey buddy. I never saw you had this thread. Not a lit of people drive a KJ here. You should honestly head over to jeepforum.com. They have a better range if jeeps people drive. If this were happening on an XJ, it sounds close to a TPS issue or the TV cable needs adjusting. Again, I don't know if the KJ has that setup since it isn't the 4.0 but rather 3.7. Good luck

 

i wish it was a rambler 4.0 but, it is not... yes quiter but not that powerful as it seems.
i dont like jeepforum. may be i am wrong, i sometimes feel that some of forum members think they know everything but not aware of what they didnt.

 

Lol. I feel if they put the 4.0 in the 02-06 cherokee(liberty) it would be more popular even with the IFS. Not a fan of the nitro platform. As for jeepforum. I wont disagree with you. Only downfall for you is, this forum never caught on with the KJ or the KK. Not sure why. People dont like em. I don't hate em. My qualm is they are dodge based. And the recall on the upper ball joints sucks. Idk.

 

You DO know why they got rid of the 4.0, don't you? It's too long, too tall, and too heavy for today's body styles. It also is a dinosaur in an age of high-reving, high strung, small displacement fuel sippers. It would be like putting a tractor engine in a sports car. Well, to be honest, MG did just that a LONG time ago! LOL!

Honestly, the 4.0 is just about maxed out in ways to make it more economical. JMHO.

 

Of course. No way to make it more fuel efficient for today's standards. And all the newer mid size SUVs are as.compact as the could be in the mid 00s. And all the new rav are these "CUV" with front wheel drive. I'm just happy the 4.0 is as reliable as it is

 

When I went looking for my jeeps, I wanted the 4.0 & the 242 t/case. I wanted something I could trust to last.

 

I have a 2007 KJ. Never had any problems like you describe. I'd suggest lostjeeps forum. It is a forum primarily for KJ and KK Liberty / Cherokee Jeeps.