Why is the car's water temperature not rising?
2 Answers
The reason why the car's water temperature does not rise is due to a faulty thermostat or a constantly running cooling fan. The thermostat operates based on the engine's water temperature. If the thermostat malfunctions and the valve fails to close, the coolant will continuously circulate in the large loop, potentially causing the engine's water temperature to remain too low. For electric fans, circuit malfunctions can cause the fan to run continuously. For viscous fans, a damaged viscous clutch can also lead to the fan running constantly. These issues can all result in low water temperature. The reasons for high car water temperature include: 1. Insufficient coolant; 2. Faulty cooling fan; 3. Malfunctioning circulation water pump. The car radiator consists of an upper tank, a lower tank, cooling tubes, and cooling fins outside the tubes. Hot coolant cools down by dissipating heat to the air, while cold air warms up by absorbing the heat from the coolant. Therefore, the radiator acts as a heat exchanger.
In my first three years of driving, I encountered an issue where the engine temperature wouldn't rise. It happened during winter short trips, with the temperature gauge needle stuck in the cold zone. The mechanic told me the most common cause is a thermostat stuck in the open position, preventing the coolant from heating up. A faulty sensor might also give false low-temperature readings. If left unfixed, an engine running too cold wastes fuel and makes overtaking dangerous due to insufficient power. Last year, I tried replacing the thermostat myself - it's a simple DIY job costing just tens of yuan for the part. Now I've developed a new habit: driving for at least ten minutes after startup to properly warm up the car. Normal operating temperature should be around 90°C; consistently lower readings warrant inspection to prevent accelerated engine wear. Never skimp on this routine maintenance.
