Originally Posted by James_V35

Ok have ruled out blown or leaky headgasket between 3 and 5. There is just nothing to suggest it could be this, just a coincidence they are next to each other. No coolant mixing with oil, no coolant or oil loss, never overheated, no white smoke from exhaust, runs smooth. Ruling out cracked or warped head too, no oil or coolant leaking from engine anywhere, engine externals completely clean and dry.

I'm thinking it's the rings. Not sure how hard it is to change the rings?

Regarding the smoke, looks like it is deposits being blown from the exhaust under high pressure and not fuel, not rich enough and doesn't smell like unburnt fuel at all. Could be clogged cats? I had a huge amount of carbon buildup which I had cleaned out a while back.

Haven't pulled the plugs out, had them replaced about 5000 ago because I had oil pooling, had it fixed up. Other than that I think the plugs were ok.