Its from first to second up-shift.

Unfortunately there isn't a hill in FL big enough to give even a geo metro a problem. However it is true its a pain to get onto the country roads in Ocala when everyone is hauling *** and u gotta get into traffic. So it was as accurate an example I could give the guy.

 

Sorry guys, I haven't posted codes 'cause I never got the codes. Problem still persists, just about every day. Did discover that it mostly acts up if I have to go down hill. Never happens after the car is warmed up, even if it sits all day while I'm at work. Just an overnight morning commute occurrence that happens more often if I take the windy back road, than if I take the flat toll road.

Also I noticed another nuance: The actual hard downshift feeling happens, and THEN the engine light comes on. I found out, if I turn off the engine and restart before the engine light comes on (there's a delay of 30 seconds or so), the engine light never comes on at all. I believe this means that the actual downshift doesn't trigger the light, but the inability to shift up after it gets stuck does. If I'm making sense.

Anyway the light doesn't stay on all day, so I've been unable to get it into the shop with the code present. I'm taking it in soon because of the ignition problem I described in another thread. Hoping I'll be able to show them this too while I'm there.