i have a 92 jeep xj and just today i decided to show off to some girls and went up this steep hill climp put the tranny if park so i could get out and take some pics when i got in the jeep to pull it down the hill it would not go into gear was like it was stuck in park or something so then reved it up to like 4 grand and it came down the hill no problem. well i got into it earlier today and all of a sudden when the jeep hits 4grand it studers really bad and want go over 4 grand untill you hold it there for like 5 seconds then it makes a weired noise like its bouncing off a rev limiter when it its nuetral it revs up to like 6 without a problem the motor is pretty built i can turn 6800 with it floored no problem. i make all my power at about 3900 to about 6 grand so this is a big problem for me if you guys could please get back with me and throw some of yalls ideas on what it might be that would be amazing im thinking tranny but don't want to think that lol so please throw some stuff my way thanks a lot guys
dakota
outlawcustoms

 

sounds like you broke something in your tranny and possibly your brain

 

I would quit taking it to 6800 rpm if I were you. I don't even take my fully rebuilt big block mopars past 6500 unless it was built to be a high rpm engine. If its stock, unrebuilt, with higher miles, repeated blasts could ruin that 4.0. The studder might be a issue with the ignition system (tune up, distributor, etc) trying to catch up with the higher rpms and the more fuel being sent into the engine.

 

Ok, I'm not really following. Not picking on you at all but lets go through this series of events again.

You meet girls and decide to show off

You climb hill

You put XJ in park and get out.

Back in XJ and won't go into gear. (That sounds like the parking pin was jammed. Happens when you put stress against it by parking it on a hill and getting out. DID you set the parking brake when you did this?)

You revved to 4000 to do what??? I dont get it. You revved it to 4000 sitting in park or you revved it to 4000 and did a neutral drop or what?

Now that overbuilt bada$$ 4.0 is acting funny.

Engine codes?

 

Check out his profile. His 4.0 is built.

 

ok let me put this this way. when i put the vehicle in drive and floor it it stops at 4 grand and resitates like it does not want to go over 4 grand makes a funny noise then it goes over 4 grand the motor is built to turn rpms without a problem

 

when i was on the hill and after i got out jumped back in and put the jeep in reverse when i did this nothing happend like you said parking pin gets stuck from time to time when you put lots of weight on them on a hill or incline however i did use the e brake when i did this so kept it in reverse and reved it up to 4 grand then the jeep went back into gear thats not the problem however i know why it did that the problem is now all of a sudden when i get into the jeep and it hits 4 grand it resitates and makes a noise like its boucing off a rev limiter. the motor may just need a tune up new spark plugs new wires and new dis cap but just figured id post this and see what kinda feed back id get because the motor is built to where i make all my power at about 3900 and its kinda hard to do that when it stoping at 4 grand and acting funny. but it didnt start doing this untill i pulled up on this bank. the jeep would turn 6800 no problem and its not stock its built to ****. i did all the suspension work my self thats what im good with suspension and diesel's haven't owned a jeep untill now so figured id throw this out there. sorry about the spelling i am using a iphone to do all this but get back to me
thanks
dakota

 

i'd put it back on the hill and rev it to 6900 before pulling it into gear this time. maybe it'll move your rev limiter back up





on a serious note. i would maybe try reseting the computer and go from there.

 

It sounds like it's running out of fuel? Maybe the incline stirred crud around in the tank and its in the filter or pickup.

 

does anyone else have any ideas?

 

That sounds like whats going on to me too.

 

So it wont Rev over 4k when it's sitting in park? Bur on the road its fine?

 

no man other way around when you are in park or nutral it will turn some rpm's but when its in drive and you give it a little hell its studers up at about 4 grand makes a popin noice

 

Pull the codes my jeep does this sometimes you may have a misfire on one or more of your cylinders. Is your engine light on?

 

Does it downshift when you floor it?