Reason of Rattling:
Water vapor in the system, causing the expansion valve to rattle
High pressure on the high pressure side causes the air-conditioning pump to vibrate and rattle.
Low refrigerant addition, causing the expansion valve to rattle.
Noise from compressor operation due to high refrigerant addition
Solution:
Check the belt for cracks and replace it or adjust the tension properly.
Check whether the bearing is good or whether the contact surface is slippery if slippery bearing noise should be replaced.
Check whether the motor is working abnormally or the fan blades are not working, and replace them if they fail
Check to make sure it's in place or lock it if it's loose.
Check whether the tensioner bearing parts are in good condition, and replace them if they are abnormal
Evacuation failed, evacuate again
System clogging should be cleared to ensure that the system high and low pressure lines are unobstructed
Top-up refrigerant
Reduce the amount of overfilled refrigerant, according to the requirements of the vehicle.
