car running for 30 minutes still not blowing hot air with heater on
Check the coolant level, if the reservoir bottle is empty, fill the radiator first and top off the reservoir after, if that's your case, you do have a coolant leaking on the system, very common places for the 99 Camry is a cracked radiator (top area) and water pump leaking. The heater should work again until the ant-freezer coolant gets low in level again.
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