SOME VEHICLES MAY EXHIBIT AN UNUSUAL SQUEAK NOISE WHEN THE ENGINE IS IDLING, OR JUST AT THE MOMENT WHEN THE ENGINE IS SHUT OFF. THE NOISE MAY BE AUDIBLE FROM INSIDE THE VEHICLE IF ONE OR MORE WINDOWS ARE OPEN, OR IF ANY PASSENGER IS OPENING A DOOR TO EXIT THE VEHICLE. DUE TO ENGINE VIBRATION AND A LACK OF SEAL RING LUBRICATION, THE MESH IN THE SEAL RING (A) RIDES IN THE FLARED PORTION (B) OF THE CATALYTIC CONVERTER (C) RESULTING IN A SLIGHT NOISE FROM THE EXHAUST SYSTEM WHILE THE ENGINE IS RUNNING. THE FRICTION BETWEEN THE EXHAUST SYSTEM PARTS AND THE RESULTING SLIGHT NOISE ARE NORMAL. THIS FRICTION DOES NOT CAUSE BREAKAGE, GAS LEAKAGE, OR OTHER FUNCTIONAL PROBLEMS WITH THE VEHICLEÂ’S EXHAUST SYSTEM. DURING NORMAL VEHICLE AGING, THE NOISE LEVEL MAY CHANGE AS THE SURFACE OF THE METAL FLANGE DETERIORATES. USUALLY THIS NOISE CANNOT BE HEARD WHEN THE ENGINE IS RUNNING, HOWEVER THE NOISE MAY BE HEARD IN A QUIET ENVIRONMENT WHEN THE CUSTOMER IS OUTSIDE THE VEHICLE OR WHEN A DOOR OR WINDOW IS OPEN.
