I had the timing cover leak repaired recently in March 2018. I have always cleaned my throttle body and MAF sensor. It was time for a cleaning and found that one of the 4 bolts that holds the throttle body was broken off. I know for a fact that the dealership did this because the throttle body hasn't been cleaned since I cleaned it. Can this be drilled out? I have to get an oil change/tire rotation soon so I'll bring it up to the service manager. Also, I haven't gotten any codes of a leak or such.