2000 Dodge Intrepid, 2.7 liter V-6, 150K miles on Mobil-1 synthetic oil.
My car belches a puff of bluish-white smoke when I accelerate from a dead stop. I can often avoid the smoke plume by accelerating very gently. The engine burns about a quart of oil every 2000 miles or so (not leaking on ground).
One mechanic said it looks like valve seals - put some Mystery Oil in the crankcase. Another said it’s the PCV valve - replace it. Another said it’s the crankshaft sensor - replace it. Another says change from synthetic to conventional oil - tried it.
None of these have worked so far.
Valve seals.
When you sit at the light and idle, the airway through which the pistons draw in air is restricted by the almost closed throttle plate. Vacuum in the cylinders is relatively high, higher than when the throttle is open and the restriction is lower. That vauum can pull oil down past worn valve stem seals on the intake strokes. You’re pulling it in when you decelerate also, but the smoke is too thin and too disspated by turbulance to see while you’re moving.