Why is the engine coolant temperature low?
2 Answers
There are several main reasons for low engine coolant temperature: 1. Thermostat failure: If the thermostat malfunctions and remains open or opens prematurely, the cooling system will continuously operate in a large circulation mode or enter large circulation too early, making it difficult for the engine temperature to rise and resulting in an overcooled engine. 2. Cooling fan failure: Faults in the temperature controller, engine control unit, or wiring can cause the cooling fan to run continuously after engine startup, operate at maximum speed immediately upon startup, or activate both fans simultaneously, leading to excessive engine cooling. 3. Shutter failure: If the shutters remain stuck in the fully open position, it will cause the engine temperature to rise too slowly or result in excessively low coolant temperature.
Having driven for many years, I've found that low coolant temperature is mostly due to a faulty thermostat. During cold winter starts, the fan would roar while the engine struggled to warm up, leaving the cabin heater ineffective. I recall my old car had exactly this issue - soaring fuel consumption and lack of power, with inspection revealing nearly depleted coolant. Normal operating temperature should be around 90°C. Prolonged low temperature not only increases engine wear and affects emissions, but may also cause internal engine damage over time. I recommend regular maintenance like changing coolant every two years, checking the thermostat and fan system - minor expenses that prevent major issues. Never overlook this seemingly small problem, especially in northern winters. Pre-warming the engine for a few minutes before driving can avoid numerous troubles.
