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Why Is Your Car Overheating?

    Car overheating

    Have you ever experienced a sudden rise in car temperature meter while driving? If it were to happen to you, please remain calm. There are several reasons your car temperature meter can go up dramatically. We shall look into some of the causes of car overheating and how to overcome them in this article.

    Car cooling system

    A car cooling system plays a critical role in ensuring an optimal car temperature and avoiding overheating. If your car temperature meter gets too high or the engine is smoky, it may indicate a problem with your car cooling system.

    Symptoms of car overheating

    The following are some of the symptoms of car overheating:

    • White smoke forming at the front bonnet of the car
    • The engine temperature needle on your dashboard rising in the ‘H’ direction or entering the red zone. For certain cars, you may notice the engine temperature warning light up if the engine temperature is high
    • Charred smell coming from the engine

    Causes of car overheating

    Typically, car overheating occurs due to any engine or cooling system component problems.

    Bjak shall explain the causes of rising car temperature in our following points.

    Faulty radiator fan

    A faulty radiator fan can cause the car temperature to rise

    A radiator fan in a car engine controls the engine temperature. Therefore, a faulty radiator fan can overheat your car.

    Damage to the radiator fan can usually occur due to:

    • Problems with the wiring system of the radiator fan motor circuit
    • Damaged relay
    • Damage to the switch or car temperature sensor
    • Damage to the fan motor where the carbon brush on the fan motor is worn out
    • Blown, loose or broken fuse

    Leaking rubber hose

    Leaking rubber hose

    A rubber hose is a crucial component of a car engine cooling system. As the rubber hose is placed near the car engine, it is highly exposed to the engine heat.

    Given that the rubber hose is exposed to the engine heat, this can cause the hose to leak and, in turn, drive your car temperature to rise sharply.

    Broken car thermostat

    A car thermostat controls the amount of coolant channeled through the engine

    Car overheating is also usually caused by a damaged car thermostat.

    Therefore, if your car thermostat is faulty, it can cause the car temperature to rise.

    How do you know whether the thermostat is faulty?

    You can tell by the valve opening; consider it faulty if the valve opening is either too small or not opening.

    Leaking head gasket

    Leaking head gasket

    A leak in the car head gasket can cause gas from the cylinder to enter the coolant duct continuously when the engine is running. It indirectly causes the pressure in the coolant duct to increase.

    The high pressure in the coolant duct will push the coolant water into the reservoir until it is full before it is drained out. This decreases the amount of coolant water in the coolant duct, which, in turn, causes the car to overheat.

    Clogged car radiator

    A clogged car radiator can affect the coolant cycle in a car cooling system

    Rust deposits in the radiator duct cause the coolant water cycle in the radiator to be interrupted or clogged. The rust deposits in the radiator duct potentially reduce the efficiency and performance of the radiator.

    A clogged car radiator can affect the coolant water cycle in the car cooling system and cause the car temperature to rise.

    Do these if your car overheats

    Stop your car

    If your car temperature rises while driving, please stay calm. Stop your car at the roadside immediately.

    Turn off the engine

    After parking your car, immediately turn off your engine before opening the front bonnet to identify the cause. Failure to turn off the engine will further damage your engine.

    Open the radiator cap

    Let your car engine cool before opening the radiator cap. If you open it while the engine is still hot, hot steam may come out and cause you burns.

    Check the water level

    After opening the radiator cap, check the water level in the radiator. In this situation, your water tank will likely be dry. If it is dry, pour coolant into the radiator when the car engine is cold. Once the radiator is full, restart your engine.

    Visit a nearby workshop

    After restarting your engine, we advise you to visit any workshop for inspection immediately. Remember not to drive too fast, and please regularly check your car temperature meter.

    Maintain your car to avoid car overheating

    We hope our sharing can help you identify the causes of car overheating and overcome the situation if it occurs to you.

    Additionally, ensure that your vehicle is always in good condition for safer driving.


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