What Causes Abnormal Water Temperature After a Cold Start?

[MilaLee]

Abnormal water temperature after a cold start is generally caused by issues with the engine's water temperature sensor. It is necessary to visit an auto repair shop to inspect the water temperature sensor and clean the engine's carbon deposits to resolve the problem. After a cold start, the water temperature usually normalizes within 1-5 minutes. In extremely low ambient temperatures, it may take over 10 minutes, which is considered normal. Relevant information about cold starts is as follows: 1. A cold start refers to starting the engine when the water temperature is low, typically after the car has not been used for an extended period (e.g., after overnight parking). 2. Causes of cold start issues: using high-viscosity oil in winter; excessive carbon deposits in the intake system or at the base of the intake valves, leading to an overly lean air-fuel mixture during cold starts; excessive contact resistance in the battery's connecting wires; insufficient battery charge.