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

As others have pointed out, the water vapor in exhaust and tail pipe for one. Another thing is that once the car is warm, the catalytic converter has heated up and is able to ensure any straggling fuel components complete their burn.