Engine reduced power

My car made some discontinuity like an impact at the brake when the speed is reduced.
a little bit later it give the warning "engine reduced power" and the throttle pedal become useless.
The scanner gave codes

P1779
P1795

and sometimes P0700

once the DTC are cleared the car works normally for a random time and the fault come back.
I changed three times the throttle body but the defect come back some times in six months and last time in less than 3 weeks.

could you help me please. And does the engine oil vapor, due to a small leak above the catalytic converter, causes the throttle body defection?
regards