Sounds like a solenoid isn't releasing or a pressure valve is stuck (I'm not good with auto's).
Or, you didn't reset the ECU and it's trying to run off corrupt learned data. Disconnect the battery for 15min or so. See if that changes anything.
And I have to ask, what was the initial problem that led to changing the solenoid? and is it gone atleast?
oh, and thank you for the well organized post. You've no idea how much of a delight it is to see one.