P0430 Code

[m980]

Hello Everyone, I’ve been getting a P0430 code with a check engine light on my truck.  When you clear it it may not come on for another month or so but seems to repeat eventually.  Scanner seems to point to an issue on the Bank 2 side of the engine.  Seems to point to the cat, or one of the O2 sensors reading incorrectly.  Anyone else have this issue and and recommendations on what to try?  I have seen some other threads with this code but it seems other codes were present at the same time.  Any ideas would be greatly appreciated.  Thanks.

[Supreme Pizza]

What Are the Symptoms of Code P0430?

• Check Engine Light is on
• Lack of power from the engine
• Decreased fuel economy
• Rotten egg or a sulfur smell

What Is the Cause of Code P0430?

• Faulty oxygen sensor
• Faulty air-fuel sensor
• Worn or internally failing catalytic converter (Most Common)
• A leak in the exhaust system
• Misfire (the root cause of converter failure)
• Rich or Lean air-fuel ratio (the root cause of converter failure)
• Leaded Gasoline (the root cause of converter failure)

[TJay74]

P0430 is because the post cat O2 sensor is saying the ECM doesnt think the catalytic convertor is doing its job. Either gonna be a bad cat (under warranty for 8yrs or 80k miles per Federal requirement) or a bad downstream O2 sensor or a bad harness to the downstream O2 sensor.

[owens sheppard]

On 12/27/2021 at 10:29 PM, TJay74 said:

P0430 is because the post cat O2 sensor is saying the ECM doesnt think the catalytic convertor is doing its job. Either gonna be a bad cat (under warranty for 8yrs or 80k miles per Federal requirement) or a bad downstream O2 sensor or a bad harness to the downstream O2 sensor. basketball stars

I think the information you bring has helped not only me but also many others.

[Shadow Fight]

On 12/27/2021 at 8:29 PM, TJay74 said:

P0430 is because the post cat O2 sensor is saying the ECM doesnt think the catalytic convertor is doing its job. Either gonna be a bad cat (under warranty for 8yrs or 80k miles per Federal requirement) or a bad downstream O2 sensor or a bad harness to the downstream O2 sensor. shadow fight

i am doing the same product that you can use,,,

[m980]

Hello Everyone, digging up an old thread of mine.  I am still having issues diagnosing a P0430 issue on my Silverado 5.3.  The light is not on all the time, sometimes if I clear it it will stay off for a while or if you just drive with it on for a while it will turn off again on its own.  It seems like the light triggers sometimes when cruising at lower speeds for an extended period of time. 

 

Since my last post, I have replaced the catalytic converter/Y pipe, replaced the O2 sensor and MAF sensor cleaned.  The voltage in O2 Bank 2 Sensor 2 was all over the map before the cat was replaced but corrected to closely mirror O2 B1S2 once the cat was replaced.  The fuel trim also observed through my scan tool looks consistent.  There are no apparent misfires that I can detect or any misfire codes thrown.  Any other thoughts or has anyone else run into this issue?

[silveradosid]

did you use oem parts, aftermarket cats don't seem to work

'

[m980]

I always use GM parts, which I did for the O2 sensor, however, I did not replace the catalytic converter with an OEM one.  I used one from Walker.  I know these aftermarket cats will not last as long as an OEM one, however, I would definitely hope it would work for over 10000kms

[loinse bekean]

Since the code could also be related to the O2 sensors, you should check the bank 2 upstream and downstream oxygen sensors. These sensors play a crucial role in monitoring the exhaust gases and can affect the catalytic converter's efficiency.

drift hunters

[Rusty Shackleford]

Switch the Bank 1 O2 sensor with the Bank 2 sensor, see if the problem moves to Bank 1. If it doesn't, your problem is not the sensor itself. Then your looking at harness or cats again.