1997 Honda Accord SE 2.2L Automatic 140k Miles
I have done much research, and I have heard everything from a simple sensor replacement, to a transmission overhaul.
Here are my symptoms
Check Engine Light reading - O'Reillys - Shift Solenoid A Electrical, Autozone - Stuck in 4th gear

D4 Flashing, so far only sometimes in the morning when cold.
In the morning, going from park to D4 there is a unusual delay in response. As the day goes on and the car heats up, the problem no longer exists.
In the morning, shifting from 1st to 2nd it seems to rev down much slower after the shift has occurred. This, as well, does not apply as the day warms up.
Everything shifts normally after a small amount of time driving.

 

Check the wiring to the shift solenoid, verify it is undamaged, also verify the connectors are not corroded. A simple test of the solenoids is to check that each one makes an audible click when directly hooked up to a 12V(battery) source. If they click they are working.

If the fluid has never been changed, do so. Dirty fluid will affect how the transmission operates.