Speaks to the bulletproof-ness of the 1GR I guess?

So I finally changed my long overdue plugs a few days ago. Been watching the fuel mileage slowly but steadily decline as the idle got rougher. Not having a garage anymore sucks. But I finally came across some free time on a sunny day and did them.

To my dismay, I found the sight pictured below. Never threw any misfire codes or anything, just chugged right along. It did idle pretty rough for the day or two before I changed em, but that’s the only indication I got that *newsflash* it was time for new plugs. But not even “down a cylinder” rough

No piston carnage observed thru the plug hole, and it doesn’t appear to be a new break. Guess it must have gotten blown out the exhaust. They’re Denso plugs.

 

Holy shit

 

What’s the mileage?

 

Just wow! How many miles on the plugs?

 

Yikes! Did you scope the cylinder?

 

Can’t say I’ve seen that.
I looks like it got broken off at some point?

If they were all Denso plugs, they were changed at least once.
Maybe the previous guy dropped the plug down the tube. Which in turn made the ground strap weak at the weld?

 

OP bout to wake up in the middle of the night randomly wondering if the plug tip is just waiting in the chamber to unleash hell on that piston.

 

The way there colored from heat almost looks like two different plugs, Denso/NGK
Originals.

 

I feel like it would have already happened

 

To clarify, these aren't the original plugs, I typically do change them with NGK or Denso every 30-35k-ish

About 185k, probably about 50k on the plugs

Oh believe me, I've had a few moments of deep reflection on the impending doom. But yeah, I figure if it was gonna grenade it would have by now. Power and fuel mileage slowly came back after the swap as the ecu re-learned everything. Was much smoother right away

 

where is the other piece

 

I don’t have access to a scope, but I didn’t see any scoring or spalling on the piston face(happened to be at a good depth to see a good portion of it thru the hole). At this point I’m just crossing my fingers that it passed harmlessly out the exhaust

 

that’s the million dollar question. Lol. Right now I’m content with “outta sight and outta mind”.

 

ping-ponging around the combustion chamber

 

My first plug change on my new to me 4.0 was similar. 0.090 gap, worn evenly. Biggest wore gap I've ever seen. Engine running smoothly. Worse things have been digested thru a cylinder than the probably paper thin relatively malibal wore down tip. I wouldn't stress over it. Like was said probably spit it out long ago.

 

Hopefully, stuck in the catalytic converter....

 

I’ve seen similar, the ground electrode wore away. Yours is broken off. Notice the tiny nick on the center electrode.

I wouldn’t worry too much about it. The broken off part probably passed through the exhaust & now lives in the cat.