I really screwed myself. I broke off a plug at the base of the hexagonal part, which means the threads and a little more is still in the head. Any suggestions would be appreciated.

 

if ya have enough room try a reverse drill bit or an ease out ,be kinda rough but its all I can think of

 

Now we know why anti-seize if so important. Try what 25th recommended. If that doesn't work, you'll probably have to pull the head and take it to a machine shop.

 

can you get a grip on the ceramic? it should pull out with little effort because the crimp above the hex is what keeps it sandwhiched in there, and since that's broken then there's not much holding it in place. then you can maybe find a really big easy out and put it in the hole through the plug shell and back it out.

 

might try a little heat from a propane bottle to, help loosen it a little

 

Thanks for the help guys. I got it out with a propane torch and an easy out.