Spark Plug Help

[CSmith4Runnin]

Hey dudes, I have quite a problem on my hands and thought maybe some of you may be able to help. My I was changing my spark plugs and wires and the plug on cylinder 3 came out rather difficultly. When I checked it out it seems it has been rethreaded with a helicoil (looking back in my records I have found a mechanic has), but half the threads are missing on the plug. I'm guessing half the helicoil is still stuck in the head which is no bueno.
So what am I looking at here? Do I need to get a new head? Can I try re-tap it and helicoil it again?
Any and all advice is welcome

Wow sorry for the huge and crappy pics. You can see the middle plug is the one in question

 

[snow junky]

you should be able to use another coil however you might need to remove the head to install the new coil.

you could try installing that coil with red locktite on the coil and in a few weeks try removing the plug again and hope the coil doesnt come out again, thats what i would do.

 

[02SE]

I've had good luck using Timesert spark plug thread repair kits. The threads can be harder to repair with deep-set sparkplug threads like the 5VZ-FE has. But they can be repaired with the cylinder head still on the engine.

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Always use anti-seize on the threads of the sparkplug, when installing them. That's especially important for threads that have been repaired with an insert. Otherwise it's likely the insert will come out with the sparkplug, the next time you change them. I suspect that is what happened here.

 

[CSmith4Runnin]

Thanks for the replies I appreciate it. I'll try to rethread it again with another helicoil. My only question is how do I get out the threads that are already stuck in there?