What Are the Causes of High Temperature in Cars?

[Toni]

Engine's air charging coefficient decreases, abnormal engine combustion, engine oil deterioration, fuel supply system prone to vapor lock, and ignition system malfunction. Additional details: 1. Decrease in engine's air charging coefficient: Higher temperatures lead to lower air density, reducing the actual air intake of the engine; overheating of the engine increases the temperature under the hood, further decreasing the engine's air charging capability. The reduced air charging coefficient results in decreased engine power, causing the car to lose driving force. 2. Abnormal engine combustion: High ambient temperatures raise the temperature of the air-fuel mixture entering the cylinders, increasing the overall operating cycle temperature of the engine. Coupled with the radiator's reduced cooling efficiency, the engine becomes overheated. The end-gas mixture in the combustion chamber absorbs more heat, accelerating pre-flame reactions and increasing the likelihood of engine knocking. 3. Fuel supply system prone to vapor lock: Higher temperatures increase the temperature under the hood, making vapor lock more likely. When the fuel system heats up, some gasoline evaporates into gas, accumulating in the fuel lines and fuel pump, increasing fuel flow resistance and disrupting the vacuum created by the fuel pump during the suction stroke. This leads to insufficient or interrupted fuel supply, causing vapor lock in the fuel system. 4. Ignition system malfunction: When driving in high-temperature environments, the ignition coil can overheat, weakening the high-voltage spark and causing high-speed misfires. In severe cases, the ignition coil may burn out, affecting the car's normal operation.

[MacFernando]

What I fear most during long-distance driving is engine overheating and smoke. That time on the highway when the tire pressure warning light came on, the temperature gauge immediately shot up to red, nearly giving me a heart attack. The main causes are insufficient or leaking coolant, a radiator clogged with dust and bugs blocking airflow and preventing heat dissipation, or a thermostat stuck in the closed position preventing coolant circulation. Additionally, high ambient temperatures, like 40°C in summer without AC or enough airflow, can easily lead to overheating. If the belt is loose or broken and the water pump can't turn, it also affects the cooling system's operation. I recommend regularly checking the engine bay, cleaning the radiator, and topping up antifreeze—especially before long trips—and never skimping on maintenance to greatly avoid such dangers. If you notice the temperature rising quickly, pull over immediately, turn off the engine, and wait for it to cool down. Never push through, or you risk engine seizure with sky-high repair costs—a lesson I learned the hard way. Remembering these tips can save your life.

[DiKevin]

As a car enthusiast, I often tinker with components under the hood and have experienced high-temperature issues more than once. The basic causes include fan failure, the electric fan getting stuck and not turning, air cooling not working, the radiator being empty or having tiny cracks that leak coolant, and the belt tensioner failing, which can cause the water pump to stop working, preventing the system from circulating. Another common factor is a dirty air filter that can't draw in enough cold air or an overloaded air conditioning compressor causing too much load. I've tried replacing the belt and checking the fan myself—if there's unusual noise, it's a warning sign. Preventive measures include regularly changing the coolant to maintain cleanliness and adding a small auxiliary radiator for extra help, especially when driving in hot areas. Once overheating occurs, the car may suddenly lose power and struggle to accelerate, requiring an immediate stop and professional inspection—safety always comes first.

[MacRobert]

After having children at home, I pay the most attention to car safety. High temperatures can cause engine failure, and in severe cases, smoke or even engine seizure, posing significant risks. I’ve summarized the reasons: high ambient temperatures, prolonged idling in traffic leading to insufficient cooling, old or degraded coolant with inadequate capacity, depleted engine oil causing insufficient lubrication and accelerated wear, as well as malfunctioning thermostats or faulty sensors reporting high temperatures. If the air conditioning system fails and blows hot air, it can further increase the load. For prevention, I make it a habit to check the radiator and top up the coolant every six months, clean the AC filter, and monitor the dashboard closely during highway driving. If a high-temperature warning light comes on, I immediately turn on the heater to release some heat and bring the temperature down to a safe range before seeking repairs. This not only protects the car but also ensures peace of mind for family trips.

[LucasRose]

When I first got my driver's license, I was baffled by the car overheating. The reasons were actually simple, like an empty radiator—just filling it up would fix it, or a blown fuse, a broken fan circuit, or poor contact. There was also the case of accidentally not closing the hood properly, leading to poor sealing and heat not dissipating. I tried fixing it myself by removing the cover and found the radiator grille blocked by leaves, hindering air cooling—a simple rinse would do. If you're not sure how to handle it, don't mess around; drive to a repair shop to check the temperature control system to avoid costly overhauls. Such issues are common in older cars. Make it a habit to check the coolant level regularly, avoid idling for too long, drive safely, and worry less.