2007 5.3 “catalyst efficiency below threshold” bank 1 and 2??!!

[shakenfake]

That is possible yes.

 

Edit: You would need a scan tool I think to see if it is in open loop. You cannot tell just by something the truck is doing

Edited December 3, 2021 by shakenfake

[Nate6.0]

On 12/1/2021 at 11:36 PM, Grumpy Bear said:

 

Edited December 7, 2021 by Nate6.0

[Nate6.0]

I spaced the sensors out with modified non foulers…how long should it take for the CEL to go out if this is effective?

[Silverado4x4]

30 minutes ago, Nate6.0 said:

I spaced the sensors out with modified non foulers…how long should it take for the CEL to go out if this is effective?

It's like 5 restarts of the motor or you can take it to an auto parts store and have them clear the code they don't charge you.

[richard wysong]

it would be better to turn it off w the scan tool

[richard wysong]

autoparts stores aren't supposed to clear codes but you may get a sympathetic employee that will

[shakenfake]

Never been to a parts store that wouldn't clear codes haha

[Grumpy Bear]

I use my Scan Gauge II to clear the random code. 

[richard wysong]

maybe its just in Mass but I think they said the same thing in Fla

[Supreme Pizza]

So your getting codes for the bank 1 sensor 2 and the bank 2 sensor 2.  I would not even bother trying to fix it, but thats only because it will not cause any problems other than failing emissions (not required in my state). If emissions are required in your state, you may be able to just pay the $175 fine for failing the test each year and continue on. That would be cheaper than replacing a million parts. Sometimes its best to just pay a shop or the dealer to diagnose the problem rather than throwing parts at it. Since its on both banks, I would say it has to be something common to both banks with air or fuel. Maybe a vacuum leak before the TB? Maybe a plugged air filter? Hard to say.

[Nate6.0]

So today I took a drive and my early Christmas present…engine light off on its own!!!!! I guess the anti foulers worked and I don’t even have to feel too bad about the actual environmental impact because it has 2 brand new cats doing their thing, just not CARB cats…what a journey 

[Supreme Pizza]

That's good to hear. Thanks for the update.

[Nate6.0]

Yes, I was very pleased. Thank you all for the info, suggestions and tips. 

[richard wysong]

Yep thats GREAT! I have had success with that method as well, its very frustrating to spend all that $ and still have a CEL, glad we could help