2002 Kia Sedona, middle spark plug exploded, threads in the head are gone, anyone know the cause?
“Middle spark plug”?
Did the plug explode, or did it blow out of the head? The latter I’ve heard of, not the former.
The usual cause of a plug blowing out is improper installation, either by installing it too loosely or by cross-threading it and stripping out the threads.
Should have added: The repair is usually pretty straightforward. The hole is drilled and tapped, and a Heli-coil or similar gizmo is installed. The new spark plug screws into the Heli-coil.
Or overtorquing it and overstressing the threads.
Yeah, I agree. The good news is that it can be repaired readily and permanently. The hole gets a helicoil.
did you have the plugs replaced recently? if you did, take it back there and have them replace/ repair the hole they messed up.
if you have never had the plugs replaced, then this is an unfortunate oops which you need to fix anyway.
(or have fixed)