Buick PARKAVENUE 1994 Manual page 211

If
the coolant inside the coolant recovery tank is boiling,
don't do anything else until
it
cools down.
P
The coolant level should be at or above "FULL COLD."
If
it isn't, you may have a leak in the radiator hoses,
heater hoses, radiator, water pump or somewhere else in
the cooling system.
I
NOTICE:
I
Engine damage from running your engine
without coolant isn't covered by your warranty.
If there seems to be no leak, check to see if the electric
engine fans are running. If the engine is overheating,
both fans should be running. If they aren't, your vehicle
needs service.
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