The coolant will run out of the timing cover from behind the crank pulley.
If it is leaking next to where the lower radiator hose attaches to the engine, the water pump has failed. That hole is the water pump weep hole.
No, that plug is not required.
if the water pump is noisy or it is leaking coolant out the relief hole on bottom of pump.
The weep hole is next to the housing where the lower radiator hose attaches to the engine.
Yes, it is next to a bolt on the housing the radiator hose attaches to.
The rubber plug just covers the weep hole to hide any minor leakage from the water pump seal.The rubber plug just covers the weep hole to hide any minor leakage from the water pump seal.
The weep hole your talking about is for the seal on the water pump. you need to replace water pump to stop the leak. The water pump is driven by the timing chain. The entire front of the engine needs to be disassembled to access.
If you follow the lower radiator hose to the engine, you will find a plastic housing behind the alternator. The water pump weep hole is next to the lower bolt for that housing. By the way that housing is where the thermostat is located.
heater core may be leaking or hole in floor
Yes, any coolant leak is serious.
It is the threaded plug for the hole you add fuel to.
Down the hole where you pull the dipstick out of.