Chevrolet 1995 Lumina Owner's Manual page 179

3.4 L LQ1 (Code X) Engine
The coolant level should be at or above the COLD mark.
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.
If the coolant inside the coolant recovery tank is boiling,
don't do anything else until it cools down.
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