Bongani

I recently had my timing belt for my 2002 3.0L V6 Audi Quattro replaced. It had 110 000 miles and the tensioner for the serpentine belt broke and so I figured since I am replacing that I might as well take the hit of having them just change the timing belt, they are 1/4 of the way there anyway. After changing the timing belt, the check engine light came on and the code is for the cam shaft sensor. Further inspection says that the sensor is at 90%. Should I replace it and how labor intensive is it to do this?