I've seen alot of good info on changing the plugs on the 5.4 3V here and thank you to all who contributed. Changed mine with no broken ones. After about 750 miles got the flashing MIL, code reader said P0301 mil. So I pulled #1 plug and this is what I found (see pics).

Anyone seen this before? Any ideas what could have done this?

Thanks for any input you may have.


https://picasaweb.google.com/lh/phot...eat=directlink

https://picasaweb.google.com/lh/phot...eat=directlink

https://picasaweb.google.com/lh/phot...eat=directlink

 

was there a rock in there or something?

 

A piece of a broken valve or a broken piston. Unless it sucked something in through the intake. Or maybe even an injector came apart.

Regardless of what it was you might want to examine it with a bore scope and do a compression test.

Was there any noise or just a cel? And is it bent b/c in the pic it looks alittle like its melted.

 

I looked with a bore scope, it wouldn't fit all the way into the CC, but it looks like a corner of one of the valves is visible. So I think it must have bent a valve. And Yes, there was a knocking sound and a vibration when it happened. I shut it off right away and had it towed home.

Looks like tomorrow OFF WITH IT'S HEAD!!

Gezz why couldn't the plug just blow out like all the others.

 

Ouch..... wonder how much damage is done to the cylinder.

 

Yes I have seen it before and its from debris in the combustion chamber. Did you have any parts like a COP bolt missing when you reinstalled the plugs. Also if you dropped that plug the ceramic could have fractured and later broke off, it would be slammed around from the piston with enough force to damage the plug. With the borescope you should be able to see dimples on the piston dome from the debris bouncing around. A piece of valve seat, piston land, or valve will do the same thing. Just seems like a coinsidence that it happened so soon after the plug change. Good luck

 

750 miles though? My first thought was something from the plug change.. but I would think that would have showed up sooner. Whatever it is won't be good... Heads would be just one worry. Having to tear it down for a new bore and piston would be worst case.

 

It's a little hard to tell. To bad you didn't ramp the size up on those pictures. it looks to me like an injector was running lean and the thing MELTED. It actually looks like the metal is folded in down at the bottom of the ground barrel. I don't think anything that might have been left in the cylinder would survive for 750 mi. before it decided "get in the way". Definitely LOOKS melted, which isn't good!

 

That was my thought too. Could an injector breaking have caused it? 750 miles is too far to be from debris from the plug change.

 

What year is the engine?

 

looks melted and carbon build up to me

 

It does look a little melted but my eyes aren't as good as they once were. If the ceramic was just fractured it could take awhile to finally break completely off. If it went that lean then pieces of piston dome/land could have broken loose as well and damaged the plug. Also it appears to me that the ceramic is gone in that plug which is usually caused from an impact or original breakage failure. Melting should not cause the ceramic to be damaged at least not as much I don't think. There looks to be a considerable amount of damage in the form of bending/crushing to the shield as well. Maybe plug removal caused that maybe impact. Should be able to determine piston damage using the borescope. If the piston is damaged then you might as well pull the whole engine and perform the necessary repairs. JMO.

 

What would happen if the injector stuck closed? Would it not get so lean as to melt it?

 

No. No combustion, intake charge would actually cool that cylinder. That's actually how failsafe cooling works, btw.

I'm with Dyno - that looks like FOD, not melting, to me eyes.

Oopps, this ain't the Chips forum - I'm not supposed to post here

Please ignore the above.

MGD

 

Ok, and if it stuck open, would flood and not get hot enough to melt the plug.

You are forgiven. Besides, as long as it SOUNDS as if you know what you're talking about, it's all good.