Spark Plug Rust from inside

[B4ITZUP]

Changed my spark plug on saty and when I pull the plug out, the tip separate from the body and it look like it's been rusted.
Car is MY07 July 2006 Build with only 58,000 km

This seem to happen on the passenger side plugs

does anyone know what could cause this issue?

I notice there's oil in the spark plug and smell is very strong when i pulled it out, possibly from turbo, still investigating

[Dropz]

the rust forms from condensation and the normal heat they are subjected to.

The ceramic doesn't look burnt which is good.

The oil is probably from the breathers or maybe its starting to get some blow-by in the piston rings. It looks fine to me, for an old plug. I wouldn't be worried unless it uses excessive amounts of oil.

[B4ITZUP]

Thanks

oil consumption is very low

on side note, I change this plug with 1 step colder( LFR7AIX ). Not much different, slight improvement on acceleration but that could be due to the plug being new