More than likely, YES.
then you should have your radiator flushed because you have rust in it. FYI: antifreeze can strip the paint off of your it you spill it. Also, you may need to replace your radiator if the antifreeze is leaking, it may be through a rusted/corroded portion of the radiator.
Antifreeze will be leaking in the floorboard on the passenger side, there will be a smell of antifreeze through the vents.
Through the radiator cap no... But it does allow the antifreeze to come out through the cap if the pressure gets too high.
you have a hole somewhere or replaces your radiator
Blown head gasket?
You are experiencing the classic symptom of a leaking heater core. They aren't cheap. Some stop-leak in the radiator might get you through the interim if you need to budget it.
Leaking heater core.Leaking heater core.
the antifreeze runs through all your water lines in your car . . . . you put it in your water tank or radiator
It is no longer necessary to add just water to a radiator in newer cars like the 2005 Malibu. An antifreeze that is half water and half antifreeze is usually best. Add the 50/50 antifreeze to the radiator overflow tank. It should be a plastic, see through tank hooked to the radiator.
Use a 50/50 mix of antifreeze and water and fill SLOWLY to prevent an airlock through the top of the radiator
Open the radiator drain and let drain into a catch basin. Run water through the radiator by filling through the radiator cap with a hose till the water coming out is clear. Fill through the overflow bottle if there is not a radiator cap present.
Most likely the heater core is leaking. Has to be replaced.