i recently bought a 1988 cherokee that is a high miler seemed to run fine exept the idle was alittle rough I put new plugs ,wires cap rotor and did not make much diffrence so I trook off the throtle body and cleaned it out with tooth brush put it back on and now its seems to have a large hesatation that wasnt there before I also took out the little needle valve and cleaned it as well ,I am sure it was put back in the same as it came out as i counted the turns any thoughts as what I could have done wrong? thanks new to jeeps oh ya 4.0 auto 4x4

Cleaning the throttle body, did you get any solvent on or in the TPS? I would try adjusting the (needle) valve. I have an 00" XJ just looked for your "needle valve" don't see one, unless its under that module on the DS of the T-body. Also, with it running, spray a little carb cleaner or brake cleaner around the base of the T-body. If the RPM's pickup then you might have a vacuum leak at the base of the T-body.

also its seems now that it back fires through the throttle body if I floor it once in a while or it will just boog but seems to go alright when i get up to highway speed but going up hills seem to be a problem have to really acelerate to maintain speed