Ok, Here is why you should change your plugs long before the "recomended 100,000 mile interval" she has only 55K on her.

This plug was from the passenger side, all the way back. In the process of removing the coil pack, and placing a socket/extension into the spark plug well. This is what we removed. The remainder of the threads and lower electrode are still intact...in the head. This truck has been well maintained, never mudded..abused...etc. It had no prior warnings...exhast leak noise, power loss... etc. All other plugs came out ok. The coil pack was still good, no evidence of the heater hoses leaking.

TO top it all off, the night before I was rear ended by a honda civic. The ball and hitch pretty much destroyed the little 4banger. the hitch went within 10 inches of the firewall. Reciever, plug and backup lights damaged, but repairable. I drove away! they called the tow for her...was not a good weekend!

 

What's your plan to get the rest of the old plug out?
Hope all goes well.

Pete

 

Dang! That's why I change mine every 20K-30K miles.

 

It was towed to the dealership, they are assesing it now. From my conversation with the service guy, (who i know) he seemed pretty confident like it wasnt a huge deal, (kinda like they've seen it before) But not knowing what they will, do....If it were me, Id be pulling the head. The location of that last plug makes any kind of work difficult at best.

Yea, I will be changing my plugs much more often. It wasnt really that big of a deal, we only had trouble with one on the drivers side, that darn little 7mm bolt was pretty stuborn! All told, with my dad and I working on it, it would have taken us just under 2 hours, that said, neither of us had done this before on a late model F150. Dad has several on the nursery he works for (he is the lead mechianic) He voulanteered his time and tools to "learn" how to do a plug change and take his time at home. He felt pretty bad, as he was the one taking that particular plug out.

 

I was lucky mine all came out OK at 67K but I used anti-seize compound on the new plugs. Good luck with your engine...let us know how it turns out.

 

I recently did my plugs at 75K on my 4.6 and found nothing like that! All of my plugs were just severley on the electrode. Hope you get it back up and running soon.

 

That is quite a problem.

I have read a few posts around the forums about water from the heater hose dripping into that plug.
This may explain the rusted/corroded plug.

Also in my Chilton manual it warns about being cautious with that plug and what type extension you use to remove it. They mention that it is possible to cause a shear force that will cause the plug to do just what yours did.

Maybe a combo of each situation.

I changed my plugs at about 60k and the only thing I found wrong with any of my plugs was that all of them had a much larger gap than specs due to the normal wear cycle of plugs.

sorry to hear of your problem. Check the hose for water leaking into that plug after you get it fixed.

Rocks

 

That plug looks as though it was stuffed up a gopher's butt!

 

Do you get the feeling that the FoMoCo doesn't intend for you to ever see the plugs @ 100k miles? That's a pretty disheartening picture. Best of luck.

Larry

 

I know I don't want to see what they look like at 100K, mine were worn enough at 75K! I've just talked my dad into finally changing his on his Mystique, he has 115K on his factory plugs, can't wait to see what they are going to look like!

 

I did mine at 112,000. Yes, they were worn and the gap was off, but did I notice any change in performance after they were changed? No. I did however see a drop in fuel mileage after I changed. They looked nothing like the plug shown above, thats for sure!

 

I got over 63,000 on my factory plugs I was debating to change them before winter or wait but after seeing that plug I think i'll change mine out soon.

 

Cylinder head is ok, remainder of plug was removed with no damage to the threads. The are putting it back together. For those who are curious, the dealership quoted me $860 for a new head...total, less the head (including gaskets, fluids, etc...) will be in the $1200 range. Most of that is from the $89 bucks and hour labor rate!!!

 

Just to keep the fright factor in check here. That plug was not damaged due to waiting to long to change it.

The damage on that plug was from an exterior cause...such as moisture.

There are two sources for this in that cylinder.

1) and most common...heater hose leaking water into it over a prolonged period of time.

2) Condensation off of the suction line from the A/C. A poster on these forums known as Texford found this on his truck and came up with a neat solution. He insulated that line.

One more thing....don't forget that the shear force applied by using extensions combined with using an angle while trying to get plug out WILL cause the plug to break off in this exact fashion. Rusted or not.


I am glad to hear they where able to get those threads out without major surgery.
You may want to inquire as to what the chances are that some small fragments may have fallen into that cylinder. This could cause a major problem when they fire that puppy up and that piston starts acting like a thrashing machine on those metal fragments. Of course the fine boy's at Ford will fix it but you won't like what they charge.


Rocks

 

Shark,

I know that sucks, but that's what Toyota charges for just a valve job on the 3.4L V6.

Pete