What Causes High Engine Coolant Temperature When Climbing Hills?

[ReeseFitz]

The main reasons for high engine coolant temperature when climbing hills are as follows: 1. Overheating coolant gauge: When stuck in traffic or idling for extended periods, the engine coolant gauge shows excessively high temperature, the electric fan operates at high speed for too long, engine noise increases, and this issue becomes most apparent when using air conditioning in hot weather; 2. Unstable idle: When using air conditioning in hot weather, the idle becomes unstable with significant RPM fluctuations, poor acceleration response, and abnormal engine noises; 3. Engine stalling while driving: After stalling when hot, the engine may be difficult to restart after ten minutes. The vehicle may sometimes stall automatically while driving when hot; 4. Poor cooling performance: The air conditioning cools well when the engine is cold, but cooling performance deteriorates when the engine is hot. Additionally, there may be significant resonance humming in the air conditioning system.