P0741 Mercury Mountaineer 2007

Question

Hi

I have Mercury Mountaineer 2007, I had p0741 code
already i changed the gear filter, oil, solenoid, over all the gear with a new aver all kit, replaced the ecm computer, gear converter & still having the code !!!
what shall i do more pls. i start believing its something related to the engine (wrong signal or whatever )

Pls. advise.