Pre-OBD2 Catalytic Converter Verification: Ensuring Correct Application

Ensuring the correct catalytic converter is installed in pre-OBD2 vehicles is crucial for maintaining emission standards and vehicle performance. This guide provides a comprehensive list to verify the appropriate application of catalytic converters for these older vehicles. By comparing the Executive Order (EO) number stamped on the catalytic converter against this list, you can confirm its compatibility with the vehicle category.

Understanding vehicle categories is essential for accurate verification. For pre-OBD2 passenger cars, categories are divided into: PC-1, indicating vehicles with one catalytic converter per exhaust bank, and PC-2, for those with more than one catalytic converter per bank. Similarly, trucks are categorized as T-1 for models with a single catalytic converter per exhaust bank and T-2 for those equipped with multiple converters per bank. Using the correct converter, validated by its EO number, ensures optimal emissions control and compliance.

Below is a detailed table that lists Executive Orders, series numbers, vehicle categories, and manufacturers, designed to assist in the verification process for pre-OBD2 catalytic converters.

Inspection Alert

Due to a production labeling process issue, catalytic converters produced by International Muffler Company (d.b.a. Cherry Bomb/Maremont) have labels with an extra zero added to their Executive Order (E.O.) number. When the CARB issued E.O. number ends in a single digit, the E.O. label is marked as D-560-0X. Affected Executive Orders are: D-560-3, D-560-5, D-560-6, D-560-7, and D-560-8; which appear on the converter as D-560-03, D-560-05, D-560-06, D-560-07, and D-560-08, respectively. International Muffler Company is reviewing their labeling process to remove the extra zero from their issued E.O. numbers.

This labeling irregularity does not affect the performance of the catalytic converters, nor should it render the catalytic converters non-compliant or illegal during a Smog Check inspection. When verifying such E.O.s on CARB’s database, please do not input the extra “0.” Instead, type in the regular E.O. number to access a copy of the specific Executive Order in the database.

Verifying the correct catalytic converter application is more than just a regulatory requirement; it is essential for ensuring your pre-OBD2 vehicle runs cleanly and efficiently. Use this list as a tool to confirm compatibility and contribute to better air quality and vehicle longevity.