I need to remember to wear long sleeves. Every time i do it my forearm look like i fought a cat. Blood and grease mix well though so go at it.

I would use some compressed air to blow off any porcelain shards if you use the hammer method. I think that would work well, I'm just wondering if its possible to get some of the insulator to break off into the cylinder? I tend to over think things sometimes though.

You might also try lying down on the engine. This will give you a little more arm down in front of the firewall where you need it. Make sure you use silicone grease on the new boots.

I don't know how they did it but a guy i know lost a piece of sparkplug in a corsica and it pretty much put the car out of commission until they could take it apart and retrieve the piece. I would resort to that hammer method as an absolute LAST resort.

I think my left forearm is still bruised from when I replaced my plugs back in July. Like Haro said just keep at it and they will come off.

The remainder of the plug would still be in the head, blocking the plug hole.

Although remote, there is a small chance that the center electrode (or part of it) could drop into the cylinder. I have not ever had this happen, but it'* glass, and sometimes glass breaks funny. It could break parallel to the electrode, leaving a loose piece it a bad spot.

Again, I haven't ever had it happen, but I always check when i take them out.

Being that I gave it as a last resort.. I followed up and broke 6 at the mechanics shop on an old engine. It appears pretty safe and in a position of not being able to get to them and get them out..it'* a glimmer of light..

Yes..there is a chance..that one could have some other internal issue when breaking it..and that piece could get past the ground tab and go into the cylinder.