Yes, you can work on your own vehicle. That includes diagnosing and/or repairing emission problems, including replacing the catalytic converter if necessary. BUT... the information you received from the auto parts store is incorrect.
You must replace the existing catalytic converter with a CARB approved CAT designed and manufactured for your Honda Accord; even though your vehicle is out-of-state emissions certified. More than likely that is why the smog technician suggested purchasing the new catalytic converter from the Honda dealer, as the dealership will not risk selling a non-California approved CAT.
There is much confusion regarding the use of non-CARB catalytic converters as replacements on out of state (Federal 49-state) emission certified vehicles. The fact is however, in 2009, the California Air Resources Board banned the use of non-CARB complaint emission components, regardless of a vehicle's emissions configuration, if the vehicle is being operated in California.
posted by SmogTips Support 03-16-2018 04:40 PM