Luis Xavier Mayol

Can someone help me? I have an audi a4 2010, 88k miles. I took the car to the mechanic ad he found the “problem” which was the camshaft. After buying it and installing it along with the camshaft adjuster the car continued with problems. Then he disconnected the cable that goes to the camshaft adjuster magnet and the car stop failing. Do you guys know what can be the problems? I’m really anxious about this situation! Thanks