Why does the car keep overheating when driving on the highway?
2 Answers
If a car keeps overheating when driving on the highway, it may be due to a lack of water or water leakage. Specific reasons: It could be caused by insufficient coolant or water leakage. The coolant should be replenished to varying degrees every 300 to 500 kilometers of driving. It may also be due to issues with the engine's cooling system. Solutions: You can check whether the temperature sensor is providing inaccurate signals; whether the temperature gauge itself is malfunctioning and showing falsely high readings; and whether the wiring from the temperature sensor to the dashboard is functioning properly—all of these factors can affect high engine temperature. If the fan is not damaged, then check whether the thermostat is fully open. If the problem persists, it is recommended to take the car to a 4S shop for inspection and repair.
I've been driving for over twenty years and have seen many cases of high engine temperature on the highway. The most common issue is a clogged radiator or the front grille being blocked by insect remains, preventing airflow and significantly reducing cooling efficiency. Insufficient or degraded coolant also lowers cooling performance, which is particularly noticeable in older vehicles. A faulty water pump is even more troublesome—if the coolant can't circulate, you're just waiting to overheat. Last time, I encountered a stuck thermostat that wouldn't open the main cooling circuit at high temperatures, forcing me to replace it after getting off the highway. Excessive engine carbon buildup can also impair cooling, so regular cleaning is necessary. Most importantly, don't push your luck—if the temperature gauge spikes, pull over and shut off the engine immediately to avoid severe cylinder damage.
