yessureXJ jeep, USA? or ? where?NO VIN OR ENGINE TOLD AND IS A PURE ENGINE QUESTION. 4.0LITER INLINE SIX>? or 2.5?SURE MY JEEPS DID THIS VAST TIMES FROM, 1988 TO NOW. (WELL NOT MY 2010 EVER)back back long ago he ISC clogs up ever, 10,000 milesand will not idle ,lacking the IDLE AIR SUPPLYworld wide 10 engines were used XJ. sorry facts.in USA 17 digit VIN the 8th digit is engine code.or post photo of engine and i tell you whats under the hood.worst ever mistake is selling my 99' last good jeep made. IMO. (minimum of computers)1992 here is 4.0 L AMC 242or the diesel but is 94 to 02.so is 4.0 only if in USA. or 2.5L (cut down 6 to 4)owned 3 Cherokees with 4.0 drove em, 1/2 million miles, and did all the work.ONLY FAILURES WERE ISC.! best cars ever owned 1965 to now.repeatswhat I did is use magicGUN lube on the ISCoff 'd the ISCand with super special, gun lube spray for guns used in SIBERIA, "dry lube", looks like black teflonafter it dries, on the ISC cone i spray.and now ISC goes 2 or 3 times father.in truth the ISC is weaklater they went to motor drive and ended this pain.solenoid drive fails. &sticks.ISC= idle speed controller (or IAC)here it is. clean it and drivevacuum leaks cause racing engine and full powerso is not leaks.vac. 2.5L same. dealiSC-undefined-undefined-0_1.jpg