Why is it difficult to start the car when it's cold?
3 Answers
The reason is that the engine oil in the cylinders solidifies due to cold. There are two main reasons for the solidification of engine oil in cold conditions: 1. As the temperature drops, the viscosity and specific gravity of gasoline increase, and its volatility deteriorates. 2. Inadequate lubrication of friction surfaces. During a cold start, the oil pump cannot immediately deliver lubricating oil to all friction surfaces, worsening the initial lubrication conditions. 3. The lubricating oil film on the cylinder walls is damaged. Due to the low temperature, gasoline atomization becomes difficult, and some unatomized fuel enters the cylinder in liquid form, washing away the residual oil film on the cylinder walls. This deteriorates the lubrication conditions between the cylinder walls and piston rings, leading to a sharp increase in wear.
I have plenty of experience with cars being hard to start in winter. Driving an old car over a decade old, it's a headache every winter. Mainly, the battery performs much worse in low temperatures—chemical reactions slow down, leading to insufficient power that leaves the starter weak. The engine oil also thickens, making cold starts feel like pushing a boulder due to the increased resistance. Cars with better-quality oil fare better. Then there's the fuel system—gasoline doesn't evaporate well in the cold, causing ignition failures. I remember mornings when turning the key just resulted in a whirring sound but no start. After replacing the battery and switching to thinner synthetic oil, the issue was mostly resolved. My advice: check your battery life and oil grade before winter, and wait a bit longer before cranking the engine in cold starts.
As a college student who just started learning to drive, I find it particularly difficult to start the car in cold weather. In class, we learned that low temperatures can reduce the battery's discharge capacity by half because the electrolyte reaction inside slows down. At the same time, the viscosity of the engine oil increases, making the engine harder to turn over, and the starter struggles to work. In terms of fuel, cold air is denser, but poor gasoline evaporation leads to a lean mixture that's hard to ignite. I experienced a failed start in sub-zero temperatures with my family's car and later learned that regular maintenance or upgrading the battery can help. A simple solution is to turn the key to warm up the electrical system for a few seconds before starting, ensuring safety.
