You could uscrew the plug and remove it and the extension rod, and then examine why the socket gets stuck on the plug. A worn or ill fitting socket may be the problem.

If the socket does not have a detent that mates with the little spring loaded ball in the extension rod, get a better socket that has only 6 points. Do not use a 12 point socket as these are more prone to rounding the corners of hex nuts and jamming.

You may have to resort to an extraction/pickup tool. The ones I have fit over the outside of items; You need one ths fits into holes and it has to go into the 3/8 drive hole in the socket. Also, there must be enough room inside the socket above the spark plug to get the tool in there.

My first choice would be to get a good socket that comes free of the plug after it has been tightened.

If the O.D. of the socket fits too snugly with the tube, a little dirt and gum in the tube will give problems.
Get a thin wall deep socket.

Thanks, the socket is a "special" plug socket that holds the plug so it doesn't drop out when inserting the plug down a plug well. In my case I was doing a Subaru "boxer" engine, so the plugs are horizontal, and the socket's hold wasn't really needed. The real problem I think is a very old/worn extension. I'd guess the extension is at least 45 years old.

I removed the stuck plug to get the socket back, then used electrician's stretchy tape to make a couple of wraps around the extension and the socket - bingo, they stayed together for all four plugs.

Of course I had to reuse the gasket on the first "stuck" plug, and I think that is not a problem. They do crush when the plug is torqued down I suppose, but the second application was to the same or greater torque - I used a torque wrench.

Glad you got the plugs changed.

You mentioned that the special "plug gripper" socket was not needed for the horizontal layout. That special plug socket is still a good idea for horizontal plugs because a loosened plug can slid out of an ordinary socket leaving you with a chore of fishing the plug out of the hole.

When you do remove a plug (one that uses a washer) you have to make sure that the washer came out with it. An extra washer may give problems.

You can reuse the crush washer a second time. The tightening torque is the same as for the first time, but you may choose to increase the torque a little, but don't go overboard.

Had this hapen on friends 91 Escort, get a long breaker bar or ratchet and twist the socket fast as possible after a few minutes of this it will freeup and start to twist easy you can the pop it out with the ratchet or breaker bar

i tried a hanger, super glue on the rachet, put back onto the socket that is stuck on the plug and let it dry for a bit and it still won't come out? tried A KNITTING NEEDLE AND AM NOW LETTING SOME WD 40 set on it
awhile and try again in daylight!

Did you try backing the spark pug out and pulling the whole stuck mess out into the open? Or, are you saying the plug also has its threads stuck in the head?

once you get the spark plug out with the rubber insert socket.. use a different socket with the same diameter (that doesn't have the rubber insert needed to grab on the plug to lift it out of the hole) to install the new plug, then that'll lift right out when the new plug is seated into the engine block