My Transmission had the same problem. There are numberous posting on Past listings. First thing to check would be the Throttle Position Sensor (TPS). They cost about $80.00 in a Parts store.
I recommend that you purchase two of them (one spare).
Hope that this helps.
Also please provide more information on your Jeep i.e. year, size, etc.... It help others help you.
Happy Jeepin