I mean, I can read them, but I want to know what they really mean. I did some googling to try and figure out what both of these red ones correlate to but I can't find anything and I want to know if it correlates to a specific issue or part or whatever. The reason I ask is because I had a new catalytic converter installed this month, but just the one closest to the rear. The one closer to the front is one of those cheap 48 state legal ones that my dad had installed a while ago, so I'm wondering if the old cheap cat might be causing problems. Especially since I need to renew the registration soon and I live in an area that does emissions testing. Hopefully this is written clear enough and I don't just sound like a lunatic.