I drove mine (gold) for 250,000 miles . 4.0L fuel injected. one of the first for jeep.the ISC /IAC on mine failed every 10,000 miles.just gunked up,cleaned it every time and every time fixed it.RENIX french fuel injection here go easy on this wild wild ECU.(hard to find parts for that)PCV also loves to clog so clean it all. (orifice type)EGR here, the only years, 4.0L had EGR on left side of Intake man, a huge deep Intake manifold. must not be stuck open ever. at idle, it too must be cleaned.but this, old I'd replace EGR and even first hint of failing or sticking EGR.Tech answers:this engine runs off VACUUM pressure ( that MAP sensor)Map + engine load + rpm = fuel mix. called the speed density system.when it stalls and spark is good. and fuel pressure is specthenair supply is wrong, IAC IS dead. is 99% cause, mine failed 10 timesso I did this magic trick, in spray can "E&L dry gun lube."ever see what hunters uses, way way up north, hunting say Caribou.they use dry gun lube. (no wet lube allowed, all old oil cleaned off this old ISC.the spray is full of , many elements, graphite and more, that drys and lookslike teflon fry pan when done and made my jeep go 50k miles before that silly small motor ISC failed again.I spray the removed ISC cone(valve)shake can 1 full minute first.?
https://www.amazon.com/CRC-Graphite-Lube-Aerosol-Black/dp/B007I9XUD0?th=1free service manual JEEP, 8MB, and real
https://drive.proton.me/urls/Y8MTYACB8W#mahI1hurdTGP1988 version of book.ask more questions, know the 4.0L very well; I DO ,1987 to 2001.