Causes of high idle speed

1, engine carbon deposit is serious. Excessive carbon deposition in the engine is one of the common causes of idling jump. In the case of too much carbon deposit, the gasoline sprayed by the fuel injection head will be absorbed by a large amount of carbon deposit during cold start, which leads to too thin mixture during cold start and makes cold start more difficult. Clean up the carbon deposit in time, regularly clean the oil circuit at ordinary times, and check whether the idle motor works normally.

2, ignition system failure. Idle jump may be caused by ignition system failure, such as spark plug damage and need to be replaced. In addition, there may be problems with the high-voltage line and ignition coil, which can be judged by the automobile computer and then repaired in detail.

3. The oil pressure is abnormal. It may be that the fuel supply pressure or intake pressure sensor is abnormal, which causes the body to shake and needs to be repaired in time.

4, engine parts aging. The aging of engine parts, such as the aging of engine feet, will directly affect the shock absorption system of the engine, transfer vibration to the cab and steering wheel, and lead to idling, so it is necessary to replace the parts.

5. Fuel quality problems. Poor fuel quality and non-flammability will not only increase fuel consumption, but also cause idling vibration and need to be replaced.

6. The throttle is dirty. Unclean throttle will lead to the throttle opening and closing stuck, leading to idle vibration, so it is necessary to clean the throttle in time.

7. The water temperature sensor is out of order. Water temperature sensor is one of the important bases for computer to judge the working condition of engine. If it fails, the fuel injection quantity of the system will be inaccurate, leading to idle jitter, so it is necessary to repair the water temperature sensor.

8. The air flowmeter is not clean. Dirty air flow meter may lead to the decrease of air intake, which indirectly leads to the vehicle jumping when idling, so it is necessary to clean the air flow meter in time.

9, injector failure. If the fuel injector is stuck, blocked or poorly sealed, it may cause uneven fuel injection and poor atomization, and the output power of each cylinder will also be uneven, resulting in idling jump, so it is necessary to repair the fuel injector.

10, engine idle speed is low. The low idle speed of the engine itself, for example, below 600 rpm, may also cause vibration of the car body, and the idle speed needs to be adjusted.