engaged 4H in 89 XJ I just boughtv now won't go back to 2WD

I was just testing see if it would work it worked good but now when I try to put back in 2wd I still get an part time light lite... but when go down road in low vacumn conditions the lite will go out but as soon as vac comes back up it turns lite back on jacked up front and axle is locked in to transfer so what do I need to do

Reverse, neutral, shifting during a slow roll and shifting again during braking. They get stiff and refuse to shift, if they haven´t been used for awhile. Rocking, reverse and low, tried them all at one time or another.
Is the transfer hanging or is it just the axle shift motor hanging up (does the 89 have the axle shift motor?)? You can tell, when turning a corner if the transfer is still engauged, most times.
If you have a shift motor on the axle, a vaucme leak (fairly common) will mess with axle disengauge and engauge. I occasinally sprayed some WD-40 into the vacume plugs on my shift motor, seemed to help. If you go to remove the vacume lines from the shift motor, be careful plastic gets old and brittle, twist a little before pulling.

yes its an vacumn problem I think can some one tell me where to start trobleshooting this beast....lines going everywhere
I know that the axle wasn't locked when first got cherokee then now it won't release wondering about the switch on transfer case

Vacume switch on the transfer, is a possibilty, but most times, it is a sticky shift motor or a vacume leak (how is your idle). The major vacume line (like 3/8" thick) running from the manifold across the firewall, over the passengers side fender well. under the battery to the vacume resivoir (behind the bumper), is always a good place to start looking. Might want to look at the rear right, of your front axle housing and see if you have an axle shift motor there. The tubing to the shift motor, is also a possiblity. Most times mine was just a stuck shift motor, a little oil often cured the sticking.
Can´t remeber the cut off on XJ´s with the shift motor, discontinued them sometime around 90 or so.

yes has vac motor on axle has several lines there which should have vac when?

Was looking for a good drawing, best I found http://www.rightcoastcrawler.com/billaVista/2low/VAC_DIAGRAM.JPG . The red vacuum line, going from the resivoir to the vacuum switch on the transfer, should have vacuum always. One line at the shift motor, should have vacume, in 2 X. But you may have to test by trial and error. In 2X one of the lines at the shift motor should have vacume for sure.

thanks guys think thats going tobe lots of help get back with ya soon

Re: engaged 4H in 89 XJ I just bought now won't go back to 2WD

Alright here what I found
have vacumn on red line to transfer case
have two line going to roughly the end of the vacumn motor on the front axle
one has vacumn all the time no matter where transfer case shift lever is
other has no vacumn no matter where shift lever is
there is another line that goes to side of vacumn motor that has vacumn all the time
guessing that two lines on end of vacumn motor ought to switch when shift lever is moved, is this correct?
So is the switch on Transfer case bad?
is there an fix short of replacement?
how exactly does this switch work?

'few more hints . . . . wheels straight, place in reverse (make sure all is clear behind you) and hit the accellerator VERY hard . . . often, this will get it out of part time. Also, are your tires all the same height? Any w/low air pressure? Are you heavily loaded (read that, IS THE VEHICLE heavily loaded?)? All of these things can affect how or if it will come out of part time. I've never had to do this but there's also something about jacking-up one wheel and spinning it . . . . maybe someone else can help with this. Two '88 XJ Limiteds and one '91 XJ "plane jane" all w' 4.0L and AT . . . 'have had problems but have never failed to get them back out of part time . . . . good luck. Don

Ive heard of maybe one guy having to replace the switch in the last couple of years. I´d do a systematic test of the vacuum lines, plug up both ends and suck. And maybe take the shift motor off and operate it disconnected, see if the fork, moves back and forth. Spraying a little oil into the vacuum inlets for the shift motor, used to really help mine.
Caution if you try the shift motor dismounted, watch your fingers, the fork flies over to the side, fast and hard, OUCH!
Heard the vacuum switch, is fairly inexpensive, never had to change one myself, always turned out to be something else.