Smoke from exhaust from 02 highlader goes away after warm up?

Smoke from exhaust from 02 highlader goes away after warm up?
You have bad, dried out valve seals. When the engine is off, the seals dry up and allow oil to leak into the cylinder, which burns off as the somke you see on startup. But when the car warms up, oil gets back into the valve seals and they swell up enough to keep more oil from dripping into the combustion chamber, so the smoke goes away.