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It happened to me after doing an oil change, using the same oil as always the only thing that differed was the oil filter. 2 months later changed the oil again and went back to using the "Drift" filters and it was fine.

Not sure if it was pure luck, dodgy oil, dodgy filter, just thought I'd share

Get the engine compression checked and analysed by a competent mechanic- ie get a second opinion. If you cannot vouch for the engine it could have far more KM's on it than you imagine. You can find out if the car is using oil by checking distance versus mark on dipstick. Engines can burn oil under load without the driver even knowing.

Know someone that has a 2nd hand Toyota 4AGE 20V in their ICV & when they first serviced it they replaced the mineral oil with synthetic. Not smokey on startup like yours, but it used a fair bit of oil. They went back to mineral oil & oil usage was minimal.

Possibly valve stem seals. They may have gone hard.

I had that issue in a camry. Changed oil to Nulon, and after that, no smoke on start up after a few k's

But have a mechanic check it out.

chris

+1 valve stem seals if it only smokes after resting all night and clears up after.

does it smoke when being dríven at WOT?

does it smoke if you back off the gas quickly come to a stop and smoke as you pull away from a standstill (i.e. mitsubishis at traffic lights ?)

as it turns out the compression tests dont seem to show up coked up oil rings ( mine had very even psi on all four but smoked like a bugger )

from my research id try a few things.

drop the oil and make sure that there is the correct amount of oil in there. to much and they seem to smoke more

20w60 is pretty heavy weight oil fair one youve got an 89 but youve only done 150,000km happy to be told otherwise for NA's tho not sure what you guys are running

mania advised me to soak the cylinders over night with subaru upper engine cleaner to try and help with coked up rings. its hit and miss but did help a LOT with mine

and the old tried and true. drive it more and see what happens. chances are it could clear up in a couple hundred k's

oh and you may as well change out the pcv valve, if theyre jammed up they smoke and its a cheap part

+1 valve stem seals.

20W60 mineral is too thick. Yes it might stop the smoking issue. But it will slowly be killing the engine as the oil's ability to flow is reduced. It may take 50-100,000km to do so. But if you are at a stage where you need to use massively thicker oil. You're on a downward journey anyway with that engine.

The ability to flow is vastly different between mineral and synthetics. Minerals are designed for cold running, and just come out a hot running whatever. Synthetic are designed for hot running, and redesigned for cold running. Synthetics are massively better than minieral oils, as you can 100% selectively pick what the oil's abilty to flow will be hot and cold.

Old B series engine like 10W30 mineral oil from the 80s. Todays synthetic equivalent in synthetic is 5W40. And all these numbers are taking from the oils ability to flow at air temp, 40C and 100C. So if you are only having cold running issues. Then you only wanna play with the oil's ability to flow at air temp. All oil companies than all there oils data sheets available online for you to view. The abillity to flow is listed as centistokes, or cSt.