Might be a head gasket issue or cracked head but if so it will usually bubble back into the coolant overflow when you shut it off, or coolant in the oil when you do an oil change. If it is an electric fan setup it may only be working some of the time.
There are a few reasons a vehicle is overheating. The common causes are the thermostat, water pump, radiator, or the fan stopped working.
Plugged radiator, Bad thermostat, water pump not working, radiator hoses collapsing and dont forget no oil
a 2002 Alero could have several problems causing the overheating. Thermostat, water pump, or clogged radiator issues are the most common causes of overheating.
Bad radiator fan motor; bad radiator fan relay; clogged radiator; thermostat stuck closed; loose belt; bad water pump; hoses leaking;
One of the major causes of a car overheating is a leak in the cooling system. Other causes are a clogged radiator, a bad thermostat, a broken or split hose, a worn out water pump, and a faulty cooling fan.
There can be many causes of overheating. Clogged radiator, stuck thermostat, inoperable cooling fan, bad water pump, defective radiator cap, air trapped in cooling system, and blown head gasket.
Is your fan coming on?
Either the radiator is blocked, or the thermostat is stuck closed, or the water pump has failed.or it just needs water.
A bad water pump or thermostat can cause an engine to overheat. A plugged (clogged) radiator or heater core may also cause an engine to overheat.
Thermostat, water pump, radiator cap, headgasket, low coolant.
water pump. thermostat.
Low coolant, failed water pump, restricted radiator, inoperative radiator fan, thermostat,