What Causes Difficulty in Cold Starts but Normal Operation When Warm?

[DiDavid]

The reasons for difficulty in cold starts but normal operation when warm are as follows: 1. Poor fuel quality. Low-quality fuel often has poor volatility, especially during cold starts in winter when the engine block temperature is low, making fuel atomization difficult. This results in insufficient mixing of fuel and air in the combustion chamber, leading to starting difficulties or even failure to start. 2. Carbon deposits. The lower the temperature, the more fuel is required for a cold start, and the presence of carbon deposits significantly affects the success of the cold start. Carbon deposits in various parts of the engine negatively impact its normal operation. 3. Untimely spark plug replacement. Cold starts require higher ignition energy, and after a certain mileage, the electrode gap of spark plugs widens. If this exceeds the standard, the spark energy generated will weaken considerably, failing to properly ignite the air-fuel mixture in the cylinder, making it naturally difficult to start.