I have a 92YJ, 4.0 manual with 135,000. It has been running like a champ until a couple days ago. We had an extremely cold morning, and it was tough to start (New battery/starter). Once it started, I let it warm up for 15 mins before driving, had no problems. Next day there was no problems, just a little tough to get started d/t cold again. Now, even though it's warming up, it will crank just fine, hear good buzz from fuel pump, but it idles very rough... starts to idle down, then surges up...runs for a second, starts to die then idles up. I kept my foot on the accelerator to keep the RPM's up and steady, after it warmed up it seemed to run fine home. When I went to start it again, it idles down and quits. I'll start it again, it will idle down and up, surging.... Where do I start? This morning I was wondering if I was going to keep it running!