Why does your car create steam when you start it?

Answer 1

I would think if steam is coming from your vents that you have a leaking or defective heater core and or one of its components and in most cases the water leaking from the core can be found in the floor board on the passsenger side and this needs to be fixed right away due to engine coolant loss and the possiblity of engine damage from overheating. Also if the air conditioner developes a leak it could be mistaken for steam however if the freon is lost the ac will quit. , EzForJesus

heater core..

Answer 2

White smoke (steam) out the exhaust would indicate a bad head gasket or a cracked head or both.

If the steam lasts for a few minutes after your start the car and stops, it is probably just condensation. This is normal, especially in cold or wet weather.

Answer 3

you probably need a heater core.