When I replaced my spark plugs the other day I noticed my #2 plug was noticeably different than the rest. I numbered each spark plug box so I could look at them later. About 95k on the original plugs. Any reason that plug looks more worn out?

 

Jeez the electrode is basically GONE, those plugs were severely overdue. Particles of metal from both the ground strap and electrode are worn off over time from both corrosion and the friction of combustion (fast moving atomized gasses still have friction) think of a space ship re-entering our atmosphere, it's not too dissimilar.

Other than the blackness around the threads which you just corrected with new valve covers they don't look unusual, normal and expected wear as far as I can tell from the photo. Normal color, normal accumulation of impurities around the ground strap. I'm sure cylinder 2 was barely firing because that's a huge gap.

FSM states 100k interval on the plugs, the commonly prescribed wisdom is to change them every 60k.

 

Cool. Thanks for the knowledge. Sounds like I was way overdue. How about the porcelain looking a little burnt. All 6 looked the same when it came to that.

 

It's called "corona soiling" watch this video.

 

The placement of the plug's ground strap within the cylinder once it was installed could have had some affect on the #2 plug. In other words it might have had the gap facing the incoming fuel charge from the intake valve versus the other plugs having their gags angled in other directions. It's a stretch but other than the additional erosion there's not much else to go on. I agree, you definitely got your dime's worth out of that set but downside is it might have cost you some fuel mileage. Plus, it put additional load on your coils firing across both the rounded electrodes and the larger air gap. No harm but depending on how you drive the car - hard, easy or in-between, you might want to pull a couple of the new plugs at 30k-40k just to see how things are going.

 

I will end up checking them out in the future. I'm mostly curious to see how these ebay valve covers hold up. I was expecting to find oil on at least one of the plugs but to my surprise the original valve covers are still in good condition.

 

My new motorcycle uses non iridium plugs and says to replace them yearly or every 10k miles...


I upgraded to Iridium lol.

Yours were crazy toast OP!

 

I wonder how long down the road it would have been till the car started acting up. It seemed to run flawless. I did punch it yesterday though and swear it felt like some higher rpm power. Further testing will be needed! Don't want to push it too hard till I get the pcv hoses in the mail tomorrow

 

After you get those hoses do the ECU and idle reset.

 

I re-learned the idle on nissan datascan after everything was put back together. I should do it again after installing the hoses?

 

This was the only hose I was concerned about kinking causing air restriction