Wht could be wrong with my van?

i have a 1993 dode caravan sport wagon,i had a transmission pt into it and now it puts out and dies out whn im coming to a stop and boggles like its backfiring,but after a while its ok,then starts back up.i put in fuel preasure regulater,fuel pump,fuel filter,throttel posioning sensor,air idel valve,cam sensor,crank sensor,coolent temp sensor,full tune up!!!what else could it be?