Need help with a P0420 Code

[theblackduck87]

I did an engine swap a couple of years ago and have had exhaust leak issues with the shorty headers ever since until I pulled the trigger on a set of stainless works long tubes with high flow cats. New pipes all the way back to the muffler. I got the new system in, had my tune adjusted and everything was fine up till about 6 months ago. I was pushing the engine harder than usual and suddenly,"ding" and then the dreaded CEL.
It was a P0420. I checked things out underneath the truck and noticed the system had shifted a bit. I made adjustments, reset the code and all was well until last month.
I notice my tips were well past the bumper from where they were when I first installed the kit. The exhaust system had worked its way very loose and was giving me leaks at almost every joint. Spent a weekend realigning and tightening. sounded better, leaks gone. 3 days after that I got the 420 code again(Catalyst System Efficiency Below Threshold) Cleared, good for a couple of days then came back.
I hate to think that my new high flow cat has gone bad already. It is possible for the O2 sensor(s) to be going bad as they are the originals.
I want to be certain before just firing the parts cannon at it.
I made some data recordings with my Trinity 2 but cannot attach them to the post.
Is there anyone out there with a Diablo Sport data reading that wouldn't mind taking a look at these if I can manage to get them to you?

Thank you in advance.

 

[jws123]

Have a shop look at the o2 sensors and check for exhaust leaks when its running they can tell if sensors are bad or not with a scantool live data you may need new converters how many miles on your truck? I had my orig conveters on my 2011 230k never a issue but sometimes they just fail.

 

[Sherman Bird]

I did an engine swap a couple of years ago and have had exhaust leak issues with the shorty headers ever since until I pulled the trigger on a set of stainless works long tubes. I got the new system in, had my tune adjusted and everything was fine up till about 6 months ago. I was pushing the engine harder than usual and suddenly,"ding" and then the dreaded CEL.
It was a P0420. I checked things out underneath the truck and noticed the system had shifted a bit. I made adjustments, reset the code and all was well until last month.
I notice my tips were well past the bumper from where they were when I first installed the kit. The exhaust system had worked its way very loose and was giving me leaks at almost every joint. Spent a weekend realigning and tightening. sounded better, leaks gone. 3 days after that I got the 420 code again(Catalyst System Efficiency Below Threshold) Cleared, good for a couple of days then came back.
I hate to think that my new high flow cat has gone bad already. It is possi9ble for the O2 sensor(s) to be going bad as they are the originals.
I want to be certain before just firing the parts cannon at it.
I made some data recordings with my Trinity 2 but cannot attach them to the post.
Is there anyone out there with a Diablo Sport data reading that wouldn't mind taking a look at these if I can manage to get them to you?

Thank you in advance.

A 12 year old truck with original O2 sensors? Replace them and run monitors again. You might be pleasantly surprised!

 

[theblackduck87]

A 12 year old truck with original O2 sensors? Replace them and run monitors again. You might be pleasantly surprised!

OK so here is the confusing part for me...It seems that there are a few different configurations for the sensors. Some say B1S1, B1S2, and B2S1 all use the same sensor and the only one that is different is B2S2. It has also been stated that that is for the MDS set up. I swapped my engine out for a 6.4L without MDS.
Should I be looking at the sensors for the SRT Challenger?

 

[theblackduck87]

Update:... Being unfamiliar with newer electronics in vehicles I was unsure what was being discussed about different sensors for the 4 locations.
I found out ( face palm) the only difference for the O2 sensors is that the sensor for B2S2 has a longer lead than the other three.

Swapped out all 4 sensors while I was under there.
Thank you everyone who chimed in.