96_xj

Okay so here is what is going on.

The jeep drives awesome! lots of power real peppy. but here is the deal. in first second and third the moment I hit 3000 rpms exactly it drops to idle and then bucks back to life and then drops to idle and then bucks back to life. Almost like it is out of gas. None of my accessories or my electronics are effected when doing this and i cant power through it either. it will just buck and never go past 3000k. I can depress the clutch and rev it to limiter and it wont skip a beat and sounds perfect and feels good. And while driving down the road I can press the clutch in rev it up to 4000-4500 rpms and then the moment I go to engage the clutch and give power to the drive line it wont let it go past 3000k and it starts to buck again. so basically it only does it under load.


fuel pressure perfect 100% with in spec even when bucking
no codes being thrown/stored
fuel system- clean
air filter- clean
throttle boddy and components- cleaned
battery- new
spark- perfect
fuses- good
reset computer- no effect

again it drives perfect otherwise just cannot go over 3000k under load.

billfrank85

TPS?

tjwalker

I agree that the TPS could be in play here. They can conk out at a certain point in their sweep.

I would test it. You will need a manual and a meter.

I have also run into a situation where a fuel pump passes the pressure test, but fails the "capacity" or volume test. So basically it can't provide the volume of fuel needed when under load. The FSM outlines a specific test for this, so keep that in mind.

96_xj

I have the FSM. checked the volume. volume is good 100% however what is making me rule out the TPS is the fact that I can go from idle to the limiter flawlessly while not under load and can hold at any rpm for any amount of time while not under load. I am going to probe the wire and get a signal reading while at speed tho

truckntractorhick

this happened to my friend's blazer and it turn out to be a plugged cat! weird....... but maybe?

96_xj

cat is fine.

ifixit8

Any check engine lights/ codes? id check cps, and the computer connections. also on the computer it could have its mounting screws to tight going into the curcuit board.

AFARR

However, sounds identical to a problem I had in my Daily Driver (BMW 318is, '91). One of the coils was bad. Started, idled fine, but when you put it under load, it would sputter/hesitate, etc.

Since the XJ doesn't have separate coils/cylinder, might be in the wires or distributor (or even the coil itself).

AFARR

96_xj

MSD iginition and blast coils are fine.

also injector pulse is perfect. Just need to really check the TPS


ook at original post. no codes. nothing stored.

went through all connections last night.

Playboy6971

I'm having same exact problem exactly if and when u figure it out please do tell problem and I will do same

awg

Greetings to the forum Playboy

You may not have noticed that the poster last updated this thread 12 years ago

It really makes one wonder what happened here...the OP was a very experienced poster, a moderator no less, and he doesnt report back on a successful fix ?

Wonder what happened, surely he would have said if he fixed it, did he just cry in his beer and sell it as a non-goer, wreck it

Us 96 sixers got to stick together

I do not know what the issue is, one of my 96sixers used to lose power for milliseconds, but one night, I was standing outside when it did it, and I saw rear lights flicker, so my next step would have been to replace the main power cables, but some ******** ran into me instead