I just intalled a brand new Transmission on this Van but doesn't Shift from 1st

Make SURE the kick-down cable is not stuck in the downshift position! .. In other words stretched out and won't return with throttle linkage.... Pull on the cable @ throttle body to see if any 'return' spring tension can be felt.... You should feel free travel then some spring tension each time cable is pulled outward....... Throttle position sensor (TPS) can cause up-shift problems BUT it should have been like that before! .. However the kick down cable had to have been disconnected at time of transmission replacement....... You dig?