ok guys. its a bit a long story.
i had a car accident. my car swerved and it hit the pavement. the back right wheel got broken. i had to change the hub as well and all other related suspension stuff..
i didnt take it to the agency because the warrenty is expired since i don't know when..
Now the problem.
When doing over 90 km/h.. and then brake to stop it. the engine RPM remains high (15-20) when the gears shuffle down.. and if say i take off my foot from the brakes pedal the car will seem to accelerate a bit before it slows down.. i mean its as if the car pumps gas on its own while i am braking... i took it back to the same mechanic.. he connected it to the computer but nothing appears faulty..only a sensor that i am not sure of its name but it has to do with stability..
also, there is a strange sound when braking that comes from the same changed hub/wheel..

any input would be helpful

 

sounds like esp faulty you may need a speed sensor on the side wer it was damaaged....