02 explorer xls won't go into passing year

[gtice100]

When I go to pass at any speed engine rev to about 4g and won't down shift then I have to give less throttle it will then shift back to higher gear .it shifts just fine except to pass no codes

 

[transman304]

First thought is TPS but that usally will set a code. you may have to get it hooked on a scanner and have it driven and monitor inputs and output signals and go from there. Let us know what you find. Good luck