So I don’t know much about spark plugs but did I do the right thing and change them?

 

Yes those look plenty worn!

 

Ok cool glad to know. Do they just get rusty looking over time? Or is that because the coil packs weren’t sealed properly?

 

As long as you replaced them with the correct OEM Iridium Plugs it should be all good.

 

iridium plugs should last 100k+.
those are most likely the originals so i am sure some rust will develop.

 

The corrosion on the threads is water/moisture getting down through the outside. antisieze would prevent that, on the electrode its the wear from arching pitting and from being in the combustion chamber.

 

Take another look. The moisture is coming up from the engine!

 

like Hummerz suggests that's what happens with older low milage vehicles that spend most their time sitting. they need to be driven to keep moisture at bay.

 

I know with newer engines they say you can go 100K miles on a set of spark plugs but I always felt uncomfortable leaving them in that long. I change mine after 50K. Might be a waste of money but it gives me piece of mind.

 

As a new h3 owner around here. I just wanted to say thanks for all the comments and support. I know that I made the right decision changing them.