What is the reason for the loud engine idle noise and how to deal with it?

When the engine is idling, the noise is loud and the car shakes because the engine is not running smoothly. Check whether the cylinder pressure, ignition spark energy, throttle sensor, idle motor and engine pad are normal. Solution: 1. Check whether the air filter is dirty and whether the spark plug is old and must be replaced. The ignition coil is broken and the gasoline is not clean, such as water in the oil circuit. There are also this type of pump inspection and carburetor (if there is one in the car); 2, check the coolant, oil pressure is too high or too low, check the hydraulic gauge, there may be ignition time setting problems, can also lead to such symptoms; 3. Check whether the power steering oil is missing. If it is missing, please top it up. The generator bearing may be damaged. Problems with power steering pump and water pump will also produce similar noise.