Chevy Silverado and GMC Sierra Forum banner

o2 sensors and converter

415 Views 2 Replies 3 Participants Last post by  country1911
Being a novice at this I post my question as such. I have three opinions as to why my check engine light came on and all say code po430, oxygen sensor, bank 2, front, meaning I have 40% obstruction in catalytic converter. If I keep the truck as I expect to, I should enventually replace the converter. Question is, is this the solution and what is the most economical way to do it? Thanks...
1 - 3 of 3 Posts
A code P0430 may mean that one or more of the following has happened:
The catalytic converter is no longer functioning properly
An oxygen sensor is not reading (functioning) properly
There is an exhaust leak
Possible Solutions
First, inspect for exhaust leaks.
Next step is to measure the voltage at the oxygen sensor on Bank 2. In fact, it would be a good idea to test each oxygen O2 sensor while you're at it.

Read more at:
First, try troubleshooting. Swap the downstream O2 sensors side for side, if the code changes sides, replace the sensor. If not it is the converter. You need to figure out what fried the converter. Typically this is a rich condition or misfire resulting in excess fuel in the exhaust. I recommend purchasing the entire y-pipe assembly from somewhere like Replacing just a single cat would be cheaper but could be asking for issues with a cheap universal converter.
1 - 3 of 3 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.