Check out TSB 98-13-11. Beside a new software load the Servo (can't remember name, the one that's accessed from the outside bottom of the tranny. That made a big difference, just last year I did replace the TSS sensor. Just like your issue it seemed to keep the throttle pulling and then do a 1-3 shift Mine was terribly harsh on the upshift, first time it happened was in traffic jam going around Chicago. Major Saftey issue IMHO after that snafu!!!!
It still gets confused at times (mainly after interstate driving then you get into traffic, after the ATX had learned those shift patterns for several hours is when it was at it's worst), but at least it's not trying to destroy itself.
Not sure if that makes sense but I don't know the FORD ATX lingo.
Paul
Software designers and the ATX designers need to talk more.
