1990 jdm tt, Car was smoking heavily, white maybe a slight hint of blue so replaced head gaskets, stem seals reseated valves but still smoking, its run for about 2 hours since idling to see if smoke would clear. Engines now out again and there is heavy carbon on the exhaust valves particularly 1 and 2, manifold Carboned, the oxygen sensor casting coated in thick sticky oil, and there is oil coating the test pipes. Turbo exhaust side was coated but has cleaned up and it was refurbished so I'm inclined to rule this out. It was all pointing to the new valve stem seals having failed or fitted incorrectly but on removal of valves they seem tight on the valve stem.

There's clearly a lot of oil getting into the exhaust from the 2 hours it's been running.

Any thoughts on what I should look at  thanks.

Turbo oil seals....?

 

I previously had smoking issues and head work done. What actually cured it was new turbos.

Did a smoke check on the turbo oil seals and it was passing through the seals into the exhaust but spoke to Midland turbo who are always very helpful, he says this is normal if you've blocked the oil drain, in most cases its a faulty pcv preventing the oil from draining and so it will find its way through the oil seal, it makes sense with it being both sides.

Fingers crossed for you as that would be a nice and cheap fix. That is also one of the common recommendations for smoking. 

Thanks

I found this was a good help for a smoking problem: https://www.nhs.uk/better-health/quit-smoking/ 🤣

On a serious note, one of my old cars used to smoke only when deaccelerating and/or coasting downhill. Used to smoke really badly. That was the turbo seals.