Catalyst is below..

[Phoenix1970]

Hey, guys. New to the forum.
I’m looking into getting a 2022 Ram Laramie GT Sport edition.
So I’ve been getting my 2012 Ram Big horn cleaned up and what not.
My only issue that I have is the check engine light. It says Catalyst is below threshold efficiency. I have Rebuilt the engine ( 5.7L) All new O2 sensors with a brand new custom exhaust about 18 months ago. New ignition coils, spark plugs, fuel injectors, just too many modifications to list.
Is there anyone that might know why in te world it keeps coming on. I’ve done everything possible that I know of that is related to this code and it still won’t go away. NC makes you get state emissions sticker before you can renew your tags. I want to obviously trade this in to get me a newer truck , but it won’t fare well with the dealership if the check engine light is on and expired tags.
Help anyone?

 

[crash68]

It says Catalyst is below threshold efficiency. I have Rebuilt the engine ( 5.7L) All new O2 sensors with a brand new custom exhaust about 18 months ago. New ignition coils, spark plugs, fuel injectors, just too many modifications to list.

Has the catalytic converter been replaced? If the O2 sensors are good then it's most likely the catalytic converter isn't working good enough.

 

[Phoenix1970]

Yes they are brand new cats , I ad a whole new exhaust put on with the flowmaster 40 and all brand new O2s.

 

[Phoenix1970]

I checked for exhaust leaks, none found. I went ahead and made sure donuts were tightened and the exhaust manifold bolts hadn’t come loose.
Food for thought.
With a cold air intake
Stock new Catalytic Converters
3” in dual 2.5 out flow master muffler 2.5” pipes with 4”tips.
Would the stock carts maybe not be allowing enough exhaust flow and throw a code.

 

[Phoenix1970]

Has the catalytic converter been replaced? If the O2 sensors are good then it's most likely the catalytic converter isn't working good enough.

Thank you I had thought about that , being they are stock. As much as I hate to have to buy another set, may not have choice, Rt. This time get high performance I guess.

 

[Papa Red]

Welcome to the forum.

Red

 

[Harley Harrold]

 

[chopperman1]

Get some o2 spacers for the downstream sensors.