Syncmaster

We did a valve adjustment on a local s2000 this past weekend and decided to swap the plugs while we were at it. Check out the originals and let me know what you think. As far as I can see they look good, but I'm not a plug analyst by any means. From left to right, cylinders 1,2,3,4. ~40k miles on them.

zeroptzero

They look really good, I think the gap on the first plug was likely near the service limit, the center electrode looks like it had eroded faster than the others. Otherwise they look good in terms of colour and free of deposits, with no wet oil residue.

Syncmaster

Good deal, thanks! They were replaced with the OEM Honda plugs, so all should be good for a while.

shind3

What's with the specks of white on there? That's usually aluminum and a sign of detonation? Maybe someone who is more adept at reading plugs can comment.

windhund116

Those look like ash deposits from fuel additives. More than metal deposits from pre-ignition conditions.

zeroptzero

metal deposits need to be examined using a magnifying glass and bright light, you wouldn't be able to identify them in a picture so they are likely combustion deposits. Detonation related metal deposits look like little metal balls attached to the plug best viewed under magnification.