P0430 on 2015 Silverado

[trwoolsey07]

2015 Silverado with just shy of 70K miles.  Custom tune done by Lew with an AFM delete.  Nothing else aftermarket done to the engine or exhaust.  CEL came on a week ago on my drive home from work, but no operating issues noticed.  Plugged in the diablo tuner and it shows a P0430 code.  I cleared the code, but it came back this morning after approximately 400 miles.  I would think if it was an exhaust leak or bad converter it would have come back on within 50 miles, correct?  Could this be as simple as an O2 sensor starting to fail?

[Mike GMC]

Does your scanner provide live data?  If so, watch the up stream O2 sensor and compare to the other bank.  Compare the downstream 02 as well.  If bank 2 is similar to bank 1 upstream, but not down stream, it's most likely the cat that's bad.  If both banks are similar upstream and downstream but bank 2 is just over the limit, you may need get your tuner to help address it.  Either that or the other cat is just about ready as well.  If bank 2 is very different upstream from bank 1, you may have an issue with an injector or coil or even an intake/exhaust manifold leak.  

 

If you ever access to data, try and narrow it down.  If not, you may need to take it in.

[trwoolsey07]

I believe it does.  I consulted with my mechanic who let me know as long as the truck is running fine, which it is, and the check engine light is not flashing, then we will start with the easy/small things to assess.  I'll definitely be hooking up the scanner to see if I can get live data, and get an idea of what the O2 sensors are reading on both sides of the converters.

[tbarn]

Cats are 8/80 warranty I believe.

[trwoolsey07]

Update! I changed the air filter, oil, and oil filter. Truck ran for 150ish miles, and the light went away. During the time the light was on, both times, no idle/power/gas mileage issues. Very strange.