Q: How do I find out with my 2008 Honda Accord Sedan 4cyl engine is California or Federal regulated for emissions?

All cars have an emissions sticker on the core support, (radiator bracket), or on the under side of the hood. You will need to read the sticker and look for it to say California. If it doesn’t, it will be Federal emissions and will usually (but not always) say Federal. The key is, if it doesn’t say California, then it is Federal. California emissions standards are more restrictive than the Federal level. This is the reason you need to be sure.

As for which converter needs replacing, my information system states there is a different code for each converter. The converters are designated bank 1 and bank 2. I’m not sure why you need a new catalytic converter, so I can’t offer much more help here. If the shop you have it at can’t determine which one is needed, I would expect a good explanation as to why, followed by a plan to figure it out. If they can’t supply you with this, I recommend you take it to another shop for a second opinion. I find myself a little leery they are unable to tell which one you need.