99 sephia tranny issues....

i have a 99 kia sephoia automatic...it does not shift proberly when i put it in drive...if i manual shift from 1rst to 2nd to drive it is fine any body with any help to let me know where i can start let me know thanks Josh

first i wound try to change the tranny fluid and fiter.also check the kickdown cable.vales or sync in tranny may be bad but i have found most auto tranny problems come from lack of or dirty fluid.check out www.kiatechinfo.com for free tech manuals.

have your tps checked to see how muh power it's getting it only needs .5 volts!