Eli5: how come when you start your car in the cold, it “smokes” but when it warms up it stops “smoking”? The temperature outside never changed

Question

Edit: I’m talking about condensation

In: Physics

Answer 1

That’s not smoke, it’s water vapor. As your car’s exhaust system cools overnight, moisture condenses inside the tailpipe. As your car heats up, the moisture turns into steam and is pushed out of the tailpipe until it is gone.