Anyone hear of a Spark plug blowout on a 2010 4.6l 3v?

[jrford]

This is a 2010 4.6l 3v, plug has 1”/26mm of threads, so its not the two piece.

Shop replaced 6 months and 4k miles ago.

Driving on the freeway, bam sounded like I drove over something followed by very loud popping noise. Pull over and look under the hood to see passenger side coil broken and spark plug seating neatly on intake manifold. Engine spit out a sparkplug out of 1 Cylinder.

Spark plug threads looked clean, but there where white coating on the first three threads.

 

[94Eddie]

I have not heard of this happening before now with a 4.6L 3V. The 3rd gen V8s were known to do this as well as some 5.4L engines. The only logical reason I can see this happening is a plug became loose, or wasn't torque properly, and over time it worked it's way out. Is there damage done to the threads in the head?

 

[1sicbronconut]

I've repaired quite a few blown out plugs over the years (I'm a dealership tech) almost all have been early production 2v 5.4's but I have seen a few 3v's over the years both 4.6 and 5.4's there's a thread repair insert kit for the 3v's also if you need one.

 

[94Eddie]

I've repaired quite a few blown out plugs over the years (I'm a dealership tech) almost all have been early production 2v 5.4's but I have seen a few 3v's over the years both 4.6 and 5.4's there's a thread repair insert kit for the 3v's also if you need one.

Have the 4.6L 3V blow outs been with the 2005-2008 heads or the revised ones from 2009-2010?

 

[Explorer_PL]

That's the first time I hear about 3v blowouts. Fixed few of them on a friend's 2003 Explorer v8. 06-08 v8, you are lucky if you get them out LOL, but we all know that. I can see 09-10 with the one piece blow out, but like Eddie said, not torqued properly.

 

[jrford]

Shop called, when they checked it out, the threads didn't feel right on #1. They chased it a couple of times and said it was re-torqued. While they were at it, they also check the other cylinders as well. All seem to check out OK. My guess it wasn't removed cleanly and when they (he) put it back in it was fully seated.