Hello - Need Troubleshooting Ideas for Problem with my Expedition

[Pilgrim]

Your description really sounds like the early 2000s when they physically blew the plug out of the head, sometimes denting the hood. But, I don't know if this even could happen on a 2011.? You really need to get more information about the actual problem before we start guessing here.

I have the tools and have done the repairs on the early 5.4s known for blowing plugs. I've also replaced the plugs several times on the newer engines. Takes time, but not a terrible job unless you have a 2008 or earlier with the 2 piece spark plug. Anything newer should have the "good" plugs which are easy to change.

Personally, I've never replaced the boots, and never had a problem with one. My 2008 has 500,000 on it now.

 

[jim8043]

I have an older exp. and it started knocking, it was loud and metal sounding. I used an electronic stethoscope and it sounded like it was coming from everywhere. I went through valve train, stark plugs (if the plug blew out it should be loose.) it took me to timing chain and exhaust manifold. it was every where and loud. Finally I pulled the engine and tore it down, there was a bent rod, the curved side was hitting the engine block. I was lucky that it did not break or blow the side of the block out. I have never seen a rod with that much of a bend in it without breaking. Bought a complete engine kit and put it back together and have about 30k miles on it since repair.