P0430 code
Thread Starter
Melting Slicks
Joined: Jan 2017
Posts: 2,707
Likes: 897
From: CONCORD CA.
P0430 code
i have a P0430 code for several months now. i've replaced the rear O2 sensor ( both sides actually ). no change in the code.
i just replaced the catalytic convertor last weekend. again, no change in the code.
currently, i have a pending and a permanent code showing on the reader.
the mileage and power both seem to be normal.
does this code require a certain mileage or on / off cycles to clear?
i read that permanent codes have to be cleared by a tuning program.
any thoughts on how to proceed?
i just replaced the catalytic convertor last weekend. again, no change in the code.
currently, i have a pending and a permanent code showing on the reader.
the mileage and power both seem to be normal.
does this code require a certain mileage or on / off cycles to clear?
i read that permanent codes have to be cleared by a tuning program.
any thoughts on how to proceed?
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,644
Likes: 4,082
From: Cape Coral, Florida
A P0420/0430 will require 3 consecutive trips that have run and passed for the MIL to extinguish…was a CARB certified cat installed seeing you are in CA ??…sometimes only an OEM cat will work…the only DTC I know of that will not clear are certain Airbag DTC’s…I’d take the car to a diagnostic shop and let them look at the car…hopefully they know how to do an “oxygen storage” test to see if the cat is operating correctly !!..also this code is sometimes an effect and not the cause…have you had misfires where the MIL was flashing, a rich mixture, or excessive blow by ??…you have to address these conditions first or you’ll be changing another cat !!
Last edited by C5 Diag; Nov 20, 2021 at 09:14 AM.
Melting Slicks
Joined: Nov 2009
Posts: 3,301
Likes: 1,156
From: Klein TX
2023 C6 of the Year Finalist - Unmodified
2022 C6 of the Year Finalist - Unmodified
P0430 is bank 2. That's the one you changed, right? 
Seriously, how many miles on the new cat? From the shop manual:
"Note: A new converter with less than 100 miles on it may set DTC P0420 or P0430 due to out-gassing of the internal matting. Operating the vehicle at highway speeds for approximately 1 hour may correct the condition."
Seriously, how many miles on the new cat? From the shop manual:
"Note: A new converter with less than 100 miles on it may set DTC P0420 or P0430 due to out-gassing of the internal matting. Operating the vehicle at highway speeds for approximately 1 hour may correct the condition."
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,644
Likes: 4,082
From: Cape Coral, Florida
P0430 is bank 2. That's the one you changed, right?
Seriously, how many miles on the new cat? From the shop manual:
"Note: A new converter with less than 100 miles on it may set DTC P0420 or P0430 due to out-gassing of the internal matting. Operating the vehicle at highway speeds for approximately 1 hour may correct the condition."
Seriously, how many miles on the new cat? From the shop manual:
"Note: A new converter with less than 100 miles on it may set DTC P0420 or P0430 due to out-gassing of the internal matting. Operating the vehicle at highway speeds for approximately 1 hour may correct the condition."
Thread Starter
Melting Slicks
Joined: Jan 2017
Posts: 2,707
Likes: 897
From: CONCORD CA.
i have a P0430 code for several months now. i've replaced the rear O2 sensor ( both sides actually ). no change in the code.
i just replaced the catalytic convertor last weekend. again, no change in the code.
currently, i have a pending and a permanent code showing on the reader.
the mileage and power both seem to be normal.
does this code require a certain mileage or on / off cycles to clear?
i read that permanent codes have to be cleared by a tuning program.
any thoughts on how to proceed?
i just replaced the catalytic convertor last weekend. again, no change in the code.
currently, i have a pending and a permanent code showing on the reader.
the mileage and power both seem to be normal.
does this code require a certain mileage or on / off cycles to clear?
i read that permanent codes have to be cleared by a tuning program.
any thoughts on how to proceed?
i was met with a DIC display & alarm stating 'low oil pressure'. pulled off onto the shoulder, shut her off. let it sit for a minute thinking it might sensor something. no luck, just the warning ( and the gauge showing 0 psi ).
let it sit for about 20 minutes, then tried one time to start it, only to be immediately hit with a rod knock. with it being a weekend, AAA does not offer long tow ( i was about 70 miles from home ) and, the driver saying that i could ride with him ( covid ).
so, i sat in the car on the flatbed for the ride into town ( about 10 miles ).
now i get to see how good the GM warranty is. this engine is an LS3 crate i had installed last year ( 3 year / 100k mile warranty ), currently it has about 35k miles on it.
does anyone out there have any experience with a engine warranty claim? this was purchased through Jegs who provided the GM warranty info with the engine. but i'm assuming that the claim is dealt directly with GM.
happy holidays!
