AFTERMARKET CONVERTERS FOR OBDII EQUIPPED VEHICLES
Late model (generally 1996 and later) cars and trucks have On-Board Diagnostic (OBDII) systems designed to detect catalyst failures. These vehicles often use 2 or more catalytic converters and have oxygen sensors in front and behind one or more of the converters. In nearly all cases, these sensors are located in the exhaust pipe. The vehicle’s on-board computer compares the oxygen sensor signals before and after the converter(s) to determine if the converter is working correctly.
CARB California
Currently, aftermarket catalytic converters have not been officially approved by any government agency for vehicles with OBDII systems. The California Air Resources Board (ARB) does test and approve aftermarket converters and its approvals are accepted by all other states and many other countries. The ARB is developing new, tougher tests for these converters but has NOT finalized the procedure and has NOT approved any aftermarket OBDII converters. In California, no aftermarket converter company’s converters can be used on OBDII vehicles because none have been approved.
EPA National
Outside CA, aftermarket converters may be used on OBDII vehicles as long as the following guidelines are followed:
The original converter is defective as shown by emission tests, the OBDII system or the converter is physically damaged, and the converter is no longer covered by the OEM vehicle warranty.
The aftermarket converter is selected based on the vehicle weight, engine size, and physical fit.
The location of the converter must be the same as the OEM converter.
The location of the oxygen sensor(s) must be the same as in the OEM exhaust system and can not be relocated.
The diagnostic codes should be cleared according to the vehicle manufacturer’s procedure after changing the converter otherwise the on-board computer may turn on the “Check Engine” light.
Aftermarket catalytic warranty terms and conditions remain unchanged as stated on the warranty certificate.
Check Diagnostic Codes Before Replacing Any OBDII Converter. “Check Engine Light” may indicate failure other than catalyst.
