hey yall, ive been a long time lurker but im a first time poster.

ive searched and searched and havnt found anything with the problems im having. Ive had my 96 XJ for almost a year now and so far i just hit 200k this past month. Today i had to replace the dreaded ehaust manifold and i went ahead and replaced the water pump and thermostat while i was in there because i was having some over heating issues. Those are all fixed and now i have a leak free exhaust manifold finally...

well here is where the problem comes in. when i put everything together and ran it up and down the street everything seemed fine. i took it on the highway and all of that went down the drain. It seemes to struggle at high rpm's. it will lose all power and the rpms will drop and it acts like its "trying to catch itself" if you will. I can put the skinny pedal down and it wont go anywhere. so im assuming i have a vac leak somewhere. i tried the brake/carb clean spray but i cant find where a leak is. it never did this before, i still have a check engine light on and its still throwing the bad o2 sensor code so im pretty sure i still need to replace that as well, but would that be the cause of the rough idle and "loss of power"?

thanks for any help, this is my DD so i need to get this figured out ASAP

 

Well to anyone that may have the same problem I was having. I sprayed all the jnjectors where the meet the manifold with brake cleaner along with all the vac lines, and couldnt find a leak. So I went ahead and replaced the o2 sensor today and viola!!!! No more bucking, crazy idles, or loss of power at high rpms or speeds.

 

Nice work! Was it frozen in there pretty good?

 

nope, it was actually fairly easy to take out. Just used a hammer to tap the wrench once and it was done.

 

I was gonna suggest replacing it. jeep only uses speed density on theses, it has no mass air meter, meaning it relies very heavily on the O2 for feedback.

 

Yeah, that would be a bimmer, uh, I mean bummer.