I gave my 03 Neon to my son with 93k miles 2 years ago. About 6 months later(year and a half ago at 103k miles) when he was driving home from Cali, the #1 spark plug thread "sleeve" popped out. I was unable to witness the damage as I ordered a used engine and had it sent to a repair shop there for replacement($450 including shipping for a 53k mile engine was a steal). However, the mechanic told me about the "sleeve" breaking-part of it fell in and damaged the cylinder and piston. This has always bothered me and I can't find anything about it. Does the 2.0L have "sleeves" for the spark plug threads in the head?

 

They have spark plug wells but that doesn't sound like what you are talking about.. they are threaded into the head just like any other spark plug. Unless someone helicoiled the threads?..

Otherwise idk what the mechanic would be talking about..

 

I thought about that, too. But my son and the mechanic said it was like a threaded collar that had been pressed into the head. Funny thing is, it was a new car when we bought it. Maybe the head just cracked around the spark plug hole in a neat and clean circle.

 

There's a metal tube that goes into the head that keeps oil out of the spark plug wells. To get that to break and then fall into the engine (which means the plugs would have to be out)...dunno how one could pull that off.