A faulty Oxygen Sensor is a primary reason for Failure of a Catalytic Converter. Car Manufacturers Recommend Replacement of O2 Sensors at 60,000 miles. If you are purchasing a New Catalytic Converter be sure the Oxygen Sensors are Checked and Operating Correctly!
SONOMA WITH 4.3L 4WD ONLY UNDER BODY CONVERTER TEST GROUP S3G4.329GFGJ TIER1 OR S3G4.319GFEJ TIER1 CA OR NY APPROVED - CARB EXECUTIVE ORDER D280-101 PER CARB REQUIREMENTS THE TEST GROUP SHOWN HERE MUST MATCH THE TEST GROUP OF YOUR VEHICLE. CALL FOR ASSISTANCE IF NEEDED (713)722-9212