95 Cherokee really wierd starting

Read through a bunch of posts but can't find anything on this: Hot or cold, intermittently, engine will balk (almost feels like timing is way off) while starting but usually starts. Sometimes it starts better when this happens by keeping gas on the floor, then backing off as soon as the engine lights. After starting, engine idles fine but feels like it's hitting on 3cyls when throttle is depressed. (also, exhaust dosen't smell right) Checked all sensors and they appear to be ok. Spark is strong and wires etc are good. When this happens, if I re-start it, most times it runs fine and can be driven all day as long as I don't shut it off. If I do, sometimes it plays this game again, sometimes not. I've never seen this before. Anyone have a clue??