Have had this Jeep (94 5.2 litre) for a number of years. Recently (past couple of weeks) it has been surging a bit on initial start-up then as it warms up it smooths out and runs great. Then when you shut it down and try and restart warm it is difficult to get going. I checked and replaced the IAC and it had a lot of carbon build up. Checked the PCV valve and line, also gummed up and line had a crack. Replaced the PCV and line. Though it starts better and idles, still have the problem starting when warm. Suggestions on next steps? Intake air temp sensor? or ECM? Again runs fine once past the start-up issues.