Abstract: Taking the idling noise in car as research object,firstly,the noise anomaly peaks and their frequencies,which causes the excessive idling noise in car,are analyzed through the tests.Secondly,by a series of TroubleShooting tests,lock the air conditioning pipe and the beam for installing the first hanger of exhaust system as the problem points.And then,the method of test adjustment and simulation optimization is used synthetically to rectify the vibration response of the air conditioning pipe and the dynamic characteristics of the beam.Finally,the idling noise in car is improved,and reaches the target value requirements.The above research can provide reference for circumventing technological risks in the NVH performance development of the same type vehicle,meanwhile,it shows that the integrated application of test adjustment and simulation optimization technology is a fast,accurate and effective method to control the idling noise in car.

Key words: idling noise, air conditioning pipe, hanger of exhaust system