This may not be helpful but here goes: I assume it has an ATX. I had a rental car (Contour) that did this. Driving on the freeway, it dropped out of overdrive and would not go back in. Once I got off the freeway, it would take forever to get going and then SLAM into second gear. Being a rental car, I didn't try to diagnose the problem, I just called for another. I'm pretty sure what happened, first gear burnt out or the torque converter. I'm not sure about the CD4E (Contour ATX), but alot of overdive ATXs use the clutches for first and reverse for overdrive. So, when these clutches burn out, you loose overdrive and first will either slip like a MoFo or just not happen. Also, it may be the torque converter not unlocking. This is usually associated with very harsh stumbling and dying in lower gears. The car will shake like an earthquake.
Like I said, I don't know this ATX that well. My experience has bee been with GM ATXs with V8s mated to them. But I am pretty sure it is your tranny.
Good luck! Anyone else have some insight?
