Oh, that was interesting!
I had no idea that much could be read from the spark plugs.
I had the valve seals replaced this spring as it was smoking blue at warm up after sitting a couple of days.
Not sure if the new seals solved the problem as it still smokes at warm up, maybe there was old oil left since before the valve seal replacement?
So today I took the little Mopar for a spin on the highway, with a lot of full throttle accelerations up to 5000 RPM, it smoked at first but later there was not a trace of smoke when I pushed the throttle hard.
Removed spark plugs and took some pictures, it´s hard to get the colours right, but the plugs are very clean after this run and the colour is sort of grey-ish, with some changes at the ground strap bend, see pictures and inserted arrows below.
I'm still not sure of what I see, still confused but on a higher level.
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