What Causes the Engine Not to Start When the Water Temperature is High?
2 Answers
When a car's water temperature is too high and it fails to start, the issue is primarily due to component damage caused by problems in the cooling system. The car's cooling system consists of components such as the radiator, auxiliary tank, water pump, water pump belt, fan, thermostat, coolant, water passages within the engine block, and coolant pipes. In theory, a car should not be started or driven when the water temperature is excessively high. It is advisable to stop the engine and inspect the problem to prevent damage to car components that could lead to failure to start. The correct procedure when the engine is overheating due to insufficient coolant is as follows: 1. Find a safe place to pull over: Let the vehicle idle without turning off the engine, as shutting it down will stop both the cooling fan and coolant circulation, causing the engine to become even hotter. 2. Open the hood: This increases airflow, allowing the water temperature to drop. Then, slightly loosen the radiator cap to release internal steam before fully opening it. 3. Do not add coolant immediately: As physics teaches, heat causes expansion while cold causes contraction. Boiling water in a sealed container generates pressure. If the radiator cap is opened immediately after boiling, the internal pressure can cause the hot water to spray out, potentially leading to burns.
Several common factors can prevent the car from starting after a sudden rise in water temperature. Cooling system issues are the most direct cause, such as coolant leakage, which causes the engine to overheat quickly and stall upon startup. If the fan stops working due to electrical faults or motor failure, heat cannot dissipate. Additionally, a thermostat stuck in the closed position can disrupt coolant circulation. These issues lead to engine overheating, triggering the ECU's automatic protection to cut off the ignition system and prevent engine damage from explosion. I once experienced a similar situation—during summer driving, the fan sounded abnormal, the temperature gauge spiked, and the car stalled. Upon inspection, a cracked hose due to aging was found. Regular maintenance should include checking coolant levels, especially before long trips, and topping up with fresh antifreeze. If the temperature is too high, avoid forcing the engine; instead, tow the car to a repair shop to prevent chain failures.
