Please be more specific ... heater gives off heat, then cold air
OR
The heater fan runs for awhile then stops running
Perhaps it needed to cool down.
If you have lost a sufficient amount of coolant this will stop the heater working because there will be no hot water in the heater rad.
It takes less force to stop a train than to stop a car.
Motorcycles can stop faster than a car
the brakeMoreAlso losing all transmission fluid will cause your car to stop while driving.So will crashing into something.
Need to know what it is not doing, post more info.
turn off the a/c and the heater fan
the heater of your car does not only work when the car is in motion. it only works when the engine is started. you don't have a heater in your car like you do your home. the heat that you feel when you turn on your heater in your car is produced by the engine. and there for if your car is not on then you will not receive any heat. some cars take longer than others to "heat up".
Because a car weighs a lot less than a train - therefore it takes less force to stop the car.
Yes because a car doesn't have to stop at every stop
generally if anti freeze is leaking into car this indicates that the heater core is worn out and has a hole you need to replace heater core ,or lift the hood and disconect the heater hoses join the hoses together with small pipe and 2 hose clamps and the leak will stop But the heater will not work
because car in size and in mass is lighter than a train so the fact that its weight can affect the force needed to stop it so its easy to stop a car than a train .