What Causes High Idle Speed During Cold Engine Start?
1 Answers
High idle speed during cold engine start can be caused by: 1. Throttle valve sticking or failing to close properly; 2. Malfunction of the idle control valve; 3. Faulty coolant temperature sensor; 4. Air intake system leakage; 5. Malfunction of the air conditioning switch or power steering pressure switch. Idle speed refers to the engine running without load, overcoming internal friction resistance without outputting power, maintaining the minimum stable operating speed. Hazards of high idle speed include: 1. Increased engine carbon deposits; 2. Shortened engine lifespan; 3. Overly rich air-fuel mixture, potentially damaging the catalytic converter; 4. Loosening of vehicle braking components, increasing accident risks; 5. Increased exhaust emissions from engine cylinders.