99 Sport wont start, had to tow

Hey guys I posted the other week about my intermitent check engine light, and the error codes I got indicating no trans mission to the TCU, etc. The Jeep had been running fine though, and the light would come on a few days then go off a few days. Well this weekend it became very difficult to start first thing in the AM. Required several tries to start and when it would turn over it was spitting and sputtering for 5-10 sec. Then all was fine. Drove fine, shifted fine, started fine the rest of the day. Did this Sat and Sun AM. Was going to take it to the dealership this AM to have them check it out, and it wouldn't start at all! Tried for prob 10 minutes to get it to turn over. It finally smoked out of the airbox, and I called it quits and called the roll back. Had it towed to the dealer, but no word yet as they said it would be this afternoon or tomorrow AM before they could look at it. Any thoughts? It's a 99 Sport 4.0 4x4 with AW4 tranny.

-Hershey