Radiator: The radiator is the most common source of coolant leaks. Cracks or holes in the radiator can cause coolant to leak out. Inspect the radiator for any visible damage, and look for signs of leaking coolant around the base of the radiator.
Hoses: The hoses that connect the radiator to the engine and other components of the cooling system can also develop leaks. Inspect the hoses for cracks, bulges, or other signs of damage.
Water pump: The water pump is responsible for circulating coolant throughout the cooling system. A faulty water pump can develop leaks around the shaft seal or gasket. Look for signs of leaking coolant around the water pump.
Thermostat housing: The thermostat housing is located near the top of the engine and houses the thermostat. A faulty thermostat housing can develop leaks around the gasket or seal. Look for signs of leaking coolant around the thermostat housing.
Heater core: The heater core is located inside the vehicle's dashboard and provides heat to the cabin. A faulty heater core can develop leaks and cause coolant to leak inside the vehicle. If you notice a sweet smell inside the vehicle or see fogging on the inside of the windshield, it could be a sign of a heater core leak.
Head gasket: A blown head gasket can also cause coolant to leak into the engine oil or into the cylinders. This is a more serious issue that requires immediate attention. If you notice a milky substance in the engine oil or white smoke coming from the exhaust, it could be a sign of a blown head gasket.
To properly diagnose and fix the coolant leak, it is recommended to take your 1990 Toyota Camry to a qualified mechanic.
