Causes of high idle speed when Nissan Sylphy starts.

1. If the throttle does not match after the recent cleaning, the matching of the throttle will return to normal. 2. When there is a problem with the idle speed of the vehicle, it is necessary to change the oil, otherwise the engine will be abnormal for too long. 3. When the engine water temperature is low, the air conditioner is turned on, and the engine voltage is low, ECU programming should appropriately increase the idle speed. Under this normal condition, if the engine water temperature is normal, and the air conditioner is not turned on but the idle speed is high, it means that the system is faulty, which may be an electronic control system or a mechanical system.

1. If the throttle does not match after the recent cleaning, the matching of the throttle will return to normal.

2. When there is a problem with the idle speed of the vehicle, it is necessary to change the oil, otherwise the engine will be abnormal for too long.

3. When the engine water temperature is low, the air conditioner is turned on, and the engine voltage is low, ECU programming should appropriately increase the idle speed. Under this normal condition, if the engine water temperature is normal, and the air conditioner is not turned on but the idle speed is high, it means that the system is faulty, which may be an electronic control system or a mechanical system.

4. In case of high idle speed caused by mechanical failure, it is necessary to check whether the air intake pipe leaks, the vacuum tube falls off or is damaged, and the air intake pipe is damaged, because the air intake of the engine is very small when idling, and if air leaks, it will cause high idle speed.

5. Leakage of fuel injector may lead to excessive fuel supply, which may lead to higher idle speed than normal.