Range Rover County LWB (LH) V8-4.2L (1993)
Catalytic Converter: All Technical Service Bulletins
Exhaust Catalyst - Rattling at Idle
29/04/94
30/01/94/US
SUBJECT
Exhaust Catalyst Rattling
AFFECTED VEHICLES
All Range Rover Models Up to VIN RA 645570
All Defender Models Up to VIN RA 937051
MODEL
Range Rover
Defender
DETAIL
Should a customer visit your dealership with the complaint of a rattling noise from underneath the center section of the vehicle, it is possible that the
catalyst assembly is the source of the noise. This rattling noise is usually noticed with the engine idling, when hot, at a traffic light or intersection.
The cause of this rattle is most likely due to erosion of the thermal mat inside the oval (right side) cannister. This mat wraps the catalyst "brick", and may
erode due to exhaust gas flow. This will allow the catalyst brick to become loose and rattle due to movement under exhaust gas pressure pulsations.
The procedure will help you determine if the source of the noise is a catalyst, and whether the required repair is warrantable. Some catalysts do suffer
damage when the vehicles are used in varying terrains off-road, and this type of damage is obviously not warrantable.
ACTION REQUIRED