2010 Prius random misfire

Ok, sorry for the hiatus, but I have been gone for work so I haven't been able to work on the car. Anyway, I was finally able to get the exhaust off and check the catalytic converter. Looked very clogged, but I have no idea what a clear one would look like so the real test was starting the car with the exhaust system off. Though loud, the car ran great for the 30 seconds I let it idle!!!! There wasn't any misfiring that I could hear.

Now I will buy a cheap aftermarket CAT and figure out a way to plug off the coolant lines. If anyone has a suggestion on replacements I am all ears (and not in Cali, Colorado, nor New York ). Right now I am thinking worst a case scenario the car with throw code P0420, but I have read a decent amount of reviews of aftermarket ones that claim to not throw the code. They can't put anything on the internet that isn't true so they must not throw the code!

 

Not sure if this helps. Before I had taken it off I had sprayed seafoam into the O2 sensor port in the exhaust manifold which is probably why it looks relatively clean.

 

Yeah, I will be honest I have no idea why I put that. I'm not sure what I was looking at, but when I first took it off, I remember thinking it looked dirty then going back the next morning and realizing it was pretty clean.

I was holding off on Techstream since I don't believe I will ever need it again (I realize I might end up regretting that). I thought the two tests showing the exhaust manifold significantly hotter than the downstream side of the cat, along with the issue going away with the cat back off would be sufficient proof that it is indeed the Cat that is failing. Is my logic/conclusion off? I do understand that this is definitely not how one would go about working on a customer's car, but as this is my personal car I am more laxed.

 

I did, I ran it with the EGR valve unplugged and blocked. As well as unplugged and open.