hammer the throttle, it starts to move and then the engine dies down to nothing. All this happens while the carb is fully open.
it sounds like your too lean on the needles if its dieing at full throttle, richen up the needles perferably the low speed needle. and for not moving it sounds like either the brakes are dragging or the either the front or rear drive shaft needs attending to. thats the problem with a center diff if a axle looses traction you will lose all drive. i would start it up and hit the throttle and it should tell you if its the brakes or the drive shafts.
http://www.rcuniverse.com/forum/m_38..._7/key_/tm.htm
its happened to me so i think it might be the culprit click on the link and see.