Q: Overheats at 120 C even after replacing thermostat and water pump.

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Overheats at 120 C even after replacing thermostat and water pump, upper and lower radiator hoses still cold. Replaced coolant as well. Car does not get warm inside when the blowing fan is on.
My car has an automatic transmission.

If the hoses are cool, engine coolant is not flowing due to a blockage in passageways or hoses or inadequate water pump speed due to a loose drive belt. If you just added coolant after replacing the water pump and thermostat, but did not use the purge points to expel trapped air, that in itself could be the cause. Trapped air in cooling systems causes overheating because the coolant flow is blocked. Trapped air could also explain why there is no cabin heat as no coolant is flowing to the heater core. If you suspect trapped air, swerving sharply while driving can sometimes dislodge the bubble of air and get it to travel to the top of the radiator where it won’t impede coolant flow. Apart from trapped air, the radiator could be partially plugged. The water pump might not be running at engine speed due to a loose belt.The lower radiator hose could be blocked or partially collapsed. An option for you is to request an overheating diagnostic and the responding certified mechanic will get this diagnosed for you, once and for all. Once the root cause of the overheating is identified, the mechanic will let you know of the required repair.

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