What is a Cold Start?

[OVictoria]

Cold start refers to starting the engine when the coolant temperature is low, typically after the vehicle has been inactive for an extended period. For example, starting the car in the morning after overnight parking is generally considered a cold start. The causes of cold start issues in vehicles are as follows: 1. Use of high-viscosity engine oil in winter. 2. Excessive carbon deposits in the intake system or at the base of intake valves, resulting in an overly lean air-fuel mixture during cold starts. 3. Severe throttle body contamination leading to insufficient air intake. 4. Starter motor speed failing to meet requirements. 5. Excessive contact resistance in battery cables or insufficient battery charge. 6. Transmission lubricant viscosity being too thick, causing excessive engine rotation resistance. 7. Insufficient cylinder compression pressure in the engine. 8. Issues with the high-voltage ignition system—spark plugs performing poorly and failing to generate ideal sparks capable of igniting the air-fuel mixture. 9. Improper spark plug gap; malfunctioning engine coolant temperature sensor.