Removing stuck plug core from 2000 Mercury Mountaineer

I was trying to change the plugs in my Mountaineer. It has a 5.0 in it. One plug broke off between the threads and the head leaving the threaded section and part of the core in the head. What is the easiest way to remove the core without taking it to a mechanic?

There really isn’t a “easy way” to remove the plug remnant.

An Easy-out of rather substantial size may get it out after a long soak in penetrating oil - I like PB Blaster - and after you extract the core. Use a shop vac to suck up the trash from the core. You don’t want that in the cylinder. Same for the chips from the easy-out.

There is always removing the head…

If you don’t have a lot of experience working on cars…have it towed to your mechanic.

Trying to remove it and not getting the ceramic out of the cylinder can do major damage.


If you plan on replacing the plugs again, then you need to have this tool on hand.


It isn’t a 3 valve engine. In 2000 a 5.0 liter was the 2 valve pushrod engine.

Both engines used the same spark plugs.

Look it up.


I did look it up,

5.0 liter V8 in 2000 was a 2 valve pushrod that used a sparkplug (Autolite AP-4) that looked like this.

The 4.6 V8 3 valve engine used a plug (Autolite HT-1) that looked like this, and the long reach broke off in the engine requiring that Lisle tool.

The pictures clipped off the electrodes but the longer shank is clear below the threads.