Oldsmobile/Buick Repair: engine, intake manifold gasket, head gasket

Question
when pressure is put in the radiator you can hear air from under the intake manifold.
what is wrong ?
Also the water level goes down

Answer
It could be one of several things.
Blown head gasket.
Leaking intake manifold gasket.
Broken intake manifold.
Cracked head.
Leaking thermostat housing gasket or hose,(Depends on the engine, and where some of that stuff is located on it).

There must be more symptoms, like why did you blow pressure in there in the first place? Was it missing, overheating, loosing coolant, etc.
Van