275k on original spark plugs
 

I thought everyone might be entertained by a little anecdote on the durability of the OEM NGK plugs in the 2UZFE V8.

To start, this is not about my 4th Gen but family members 4th Gen. They said it was misfiring under acceleration and check engine light was on. I put my scanner on it and it was a misfire on cylinder 2. I asked when the last time spark plugs were done and supposedly they had not been done at all from when they first got it at 60,000 miles. It now had over 275,000. And I would assume it’s fairly unlikely that they got changed prior to 60,000 miles so most likely original plugs.

So I pulled all the plugs and coils. All the other coils looked perfect except for the cylinder 2 coil which had a crack and some scorching marks indicating failure. Got a new set of Denso iridium plugs and swapped all of them out as well as replacing the damaged coil.

I’ve included some pictures for those that are interested. All eight plugs looked identical to this. Really impressed that somehow these plugs lasted 275,000 miles. Also impressive that even though the gap had eroded to be fairly large, the vehicle had still driven fairly smoothly and quietly when I drove it 5k-10k miles prior to this.

Just did the plugs on my 2007 @ 240k miles.

I'm the second owner and was shocked to see original plugs!

No CEL or even rough idle but my MPG had gone way down so I figured I would do the plugs and PCV valve.

Crazy that it was running as well as it did on factory plugs

Plug gap looks like about an 1/8" or so!