What Causes Difficulty in Cold Starts During Winter?
2 Answers
There are many reasons for difficulty in cold starts, possibly due to lower temperatures of the coolant in the cooling system and the lubricating oil in the lubrication system, which can lead to hard cold starts. Below are several common causes of cold start difficulties: 1. Not replacing spark plugs in time is a common factor. Cold starts require higher ignition energy, and after a certain mileage, the electrode gap of spark plugs will increase. If it exceeds the standard, the spark energy generated will significantly weaken, making it unable to properly ignite the air-fuel mixture in the cylinder (commonly known as misfire), naturally making it hard to start. 2. Ignition coil failure is also quite common. The ignition coil is a transformer responsible for converting the vehicle's low-voltage current into high-voltage electricity, enabling the spark plug to have sufficient voltage to "generate a spark." Once the ignition coil fails, such as cracking and leaking electricity, it will cause insufficient or lacking spark plug ignition capability. Consequently, the air-fuel mixture in this cylinder will not combust, leading to engine misfire, starting difficulties, and acceleration shaking. 3. Regularly check whether the throttle body and idle valve have excessive carbon buildup. Excessive carbon buildup can easily clog the idle air passage, resulting in poor air intake. 4. Additionally, check whether the engine control system's coolant temperature sensor is functioning properly; because issues in these two areas can cause difficulties in cold starts.
Difficulty starting a cold car in winter is a common issue in my experience. It's mainly due to weak battery performance, as low temperatures cause the battery voltage to drop. Older car batteries already have reduced capacity, making it even harder to start. Another issue is the engine oil, which thickens in cold weather, becoming like congealed paste, making it difficult for the engine crankshaft to turn. Additionally, the fuel pump operates sluggishly in sub-zero conditions, leading to insufficient fuel injection and failure to ignite the engine. I once had a morning when the car wouldn't start and had to call for roadside assistance, only to find that the spark plugs were also heavily fouled with carbon deposits. It's advisable to regularly check battery health, use winter-grade engine oil in cold months, warm up the car for a few minutes beforehand, and avoid last-minute fixes.
