2003 Ford Ranger 4.0L with engine code P1717

Question

Code is p1717 and p1716.
transmission won't shift from 1st to 2nd UNLESS I remove my foot from accelerator. after that, runs fine.

valve body assembly has been replaced. Solenoids and all.

Answer 1

P1716 FORD - Transmission System Conditions
Read more: https://www.autocodes.com/p1716_ford.html

P1717 FORD - Transmission System Conditions
Read more: https://www.autocodes.com/p1717_ford.html