It will not work right.
Something is wrong. Seek professional help before you get hurt.
The remains of the old coolant can cause the new coolant to fail. Using the wrong type of coolant can also damage the engine.
one reason this may happen is as simple as the cap on your cars coolant reservoir is stripped or improperly screwed on. when this happens it doesn't allow pressure to build or hold.
Wrong mixture make sure you have pre diluted/mixed coolant/antifreeze.
No.
If only adding coolant to a leaking system it is safe because soon you will be forced to drain the coolant and fix a problem
A leak. You need to see where it is coming from.
you need to add coolant to the coolant resevoir. coolant is antifreeze. if you dont have enough in your car you can overheat and damage your engine.
possibly the coolant temp. sensor
headgasket leak and exhaust gas is getting into the coolant
Yes. Thats why every vehicle is designed to use such coolant
An incorrectly fitted radiator cap can allow coolant to escape the system.