changed out the injectors in the work truck which has had injector issues before but was under warranty then, while pulling the original set noticed that one of the hold down bolts was extremely loose so i just assumed that the dealership that did the work last time failed to tighten it. replaced the injectors with a reman set and when going back tghteningdownhold down bolts the number two injector would never tighten, the bolt started just fine but did feel loose so i tried to clean the threads back up with a tap but the there wasnt anything left thread wise on the head what would be the proper fix for this

 

Either a Timesert or Helicoil thread repair. Will be just as strong as the original threads.