Hello all! I’m asking for some thoughts on a potential problem. First, I have a 2006 F-150 XLT with the 5.4 3v engine with about 245k miles. One evening driving home the truck started to run very poorly, lack of power, had to drive with two feet just to keep it running. Check engine light on. Made it home and it immediately died. Crank no start after that. The codes lead me to believe it was a fuel issue. Having recently replaced the fuel pump I checked the FPDM. It was corroded and in two pieces hanging off the frame, so must be the culprit. Replaced it, but still crank no start. Did a lot of trouble shooting and finally decided to pull the plugs in thinking perhaps they’re too fouled. Plugs were black. I replaced them (no breakage) and in doing so followed the Hynes manual and applied nickel anti-seize to the threads (I was liberal with it). Truck started right up. Problem solved. But not for long. A few weeks later I’m getting misfires and shuttering at highway speeds. I switched the COPS to see if the misfire follows. It didn’t but got other misfires from unrelated cylinders. Before I could troubleshoot again a new problem, after running for a while not the truck would stay running at stops. Once started back up it would immediately die. It would start and stay running if allowed to cool. After some research I read that the anti-seize should be applied below the tread and above the electrode and NOT on the treads themselves since it would change the torque required and even lead to them coming loose. After checking the plugs. I was able to unscrew 4 of them by hand. I pulled them all, cleaned them and put them back in expect for #1, which I replaced. Now no misfires, no stalling. Now for the problem I found. Sorry for the long story, but not sure if all this might be related. Cylinder 1 spark plug was very bad shape. The ground bridge over the electrode was gone. Where did it go? Could it be in the cylinder? Looking down the plug bore I see a small piece of metal protruding into the bore. What is this, should it be there?






Picture of camera looking down bore. That object at the side of the bore is it.

 

I think you're seeing the rim of a valve. Notice the curve. The condition of the spark plug makes me think you have a detonation issue. Possibly from a lean condition caused by a clogged/faulty injector. Have you noticed any rattle/ping when you step into the throttle?

 

No, not since removing and resetting the plugs. If it's the rim of a valve I assume it shouldn't be where it is should it? What do you think would have destroyed the bottom of that plug?

 

The valve is in the open position. as suggested check that injector. was this the only plug on that bank that was burned out?

 

I suspect the spark plug was beaten to death from the forces of detonation, as opposed to controlled combustion.

 

Thanks all for the replies. So as far as what I see in the bore, it's just the open valve so I shouldn't be concerned, correct?
Yes, it was the only plug burned out. All others looked fine. As a side note, I was getting codes for cylinder 3 and 6 misfire, but not 1. That plug was in cylinder 1. How can I go about checking the injector? Do I have to pull it for that or do I just check with a noid light to make certain its getting voltage? Please excuse the inexperience.

 

Don't go by feel . You are definitely getting blow by, damaging plugs and boots .These are alum threads ,use a torque wrench ,check twice .
Think about cleaning out hole in cyl at spark tip with carb cleaner then that carbon will be gone . Carbon damages plugs on installation and changes heat range of plugs . Then you don't need anti seize at all , that was a temp solution before plugs were revised .
Don't go past 50k on plug change outs, always change the boots , Be careful with dirty hands with sparkplugs/boots , anti seize causes shorts . If you do use anti sieze put on nickel very thin . It can also cause heat range problems .
That carbon causes misfires .