What Causes Difficulty in Cold Engine Start?
2 Answers
There are many reasons for difficulty in cold engine start. It may be due to low temperatures of the coolant in the cooling system and the lubricating oil in the lubrication system, which can lead to difficulties in cold starting. Here are several common phenomena 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 be greatly weakened, making it impossible to normally ignite the mixed gas in the cylinder (commonly known as misfire), naturally making it difficult to start. 2. Ignition coil failure is also very common. The ignition coil is a transformer responsible for converting the vehicle's low-voltage current into high-voltage electricity, allowing the spark plug to have sufficient voltage to "generate sparks." Once the ignition coil fails, such as cracking and leaking electricity, it will cause insufficient or lacking spark plug ignition capability. Consequently, the mixed gas in this cylinder will not combust, leading to engine misfire, starting difficulties, and acceleration jitter. 3. Regularly check whether the throttle and idle valve are excessively carbon-deposited. Excessive carbon deposits can easily clog the idle air passage, leading to poor air intake. 4. Additionally, check whether the engine control system's water temperature sensor is working properly; because problems in these two aspects can cause difficulties in cold engine starts.
Having driven for so many years, I've encountered cold weather starting issues quite often. Especially in winter, the main reason is insufficient battery power at low temperatures, which slows down the battery discharge, making the current insufficient during ignition. Additionally, problems with the fuel system can occur, where the fuel pump struggles to work efficiently in the cold, leading to poor fuel supply. Spark plugs that are aged or contaminated can also fail to ignite. What's worse is when the engine oil becomes too thick, reducing its flowability and making the engine hard to move. I remember one early morning when I needed to go out, and the car just wouldn't start. After checking for a long time, I found that the spark plugs were carbon-fouled. Replacing them with new ones solved the problem immediately. I recommend regularly checking the battery life (usually replace every 3 years), adding antifreeze engine oil during autumn and winter, and turning the key to the ON position for a few seconds before starting to let the system self-check. If starting difficulties occur frequently, it's best to go to the garage for a full diagnostic scan of trouble codes. Don't delay, as it might damage the starter motor and increase repair costs.
