Catalytic Convertor ???'s
03-27-2023, 06:32 PM
#21
This thread has some good info and details on the affected VINs for the CAT problem: https://ls1tech.com/forums/pontiac-f...t-05513-a.html
my Firebird has two bad cats and was authorized to receive a free replacement. Only problem, the cats lasted 17 years before the P0420 & P0430 codes showed up.
04-20-2023, 09:18 AM
#22
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Im having the same issue on my 2001 ss m6, p0420 of course, the issue was never resolved through warranty as it only has 65k miles and the code popped up at 63k miles. Previous owner never had the code before, as he states and as the datalog shows. Cataclean makes it go away but it comes back about 250-500miles later without failure. Is my cat clogged? Ive sent about 4 bottles of cataclean through the thing now all within 1500miles. i dont notice performance changes (it still shreds through 1st, 2nd, and chirps 3rd), im thinking the efficiency is just depleted from the cat's coating as mentioned in the tech bulletin/warranty. I think the cataclean is just beating the "smell test" rather than defeating a suspected clog, since the code keeps returning so frequently. I installed an oil catch can at 64k miles as the pcv system is notorious for sending oil deposits through the intake/combustion chamber, i feel like that has reduced the frequency of the code popping up. I have an offroad ypipe and headers w/out A.I.R. injection to be installed next year along with the pcm's catalytic communications being "bypassed" with my dyno tune (im in michigan, we dont have inspections). So all of this concern will be obsolete come 2024.
Im just looking for outside validation i guess and for someone to just tell me "its ok pal" (lol) because im about to take it out of storage next week and dont want to drive it too much nor romp on it with a clogged cat. Im obsessive and insanely detailed oriented with my vehicles; to the point of neurotic. As you can probably tell
Im just looking for outside validation i guess and for someone to just tell me "its ok pal" (lol) because im about to take it out of storage next week and dont want to drive it too much nor romp on it with a clogged cat. Im obsessive and insanely detailed oriented with my vehicles; to the point of neurotic. As you can probably tell
Last edited by 01Covaro; 04-20-2023 at 09:49 AM.
04-20-2023, 01:14 PM
#23
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Im having the same issue on my 2001 ss m6, p0420 of course, the issue was never resolved through warranty as it only has 65k miles and the code popped up at 63k miles. Previous owner never had the code before, as he states and as the datalog shows. Cataclean makes it go away but it comes back about 250-500miles later without failure. Is my cat clogged? Ive sent about 4 bottles of cataclean through the thing now all within 1500miles. i dont notice performance changes (it still shreds through 1st, 2nd, and chirps 3rd), im thinking the efficiency is just depleted from the cat's coating as mentioned in the tech bulletin/warranty. I think the cataclean is just beating the "smell test" rather than defeating a suspected clog, since the code keeps returning so frequently. I installed an oil catch can at 64k miles as the pcv system is notorious for sending oil deposits through the intake/combustion chamber, i feel like that has reduced the frequency of the code popping up. I have an offroad ypipe and headers w/out A.I.R. injection to be installed next year along with the pcm's catalytic communications being "bypassed" with my dyno tune (im in michigan, we dont have inspections). So all of this concern will be obsolete come 2024.
Im just looking for outside validation i guess and for someone to just tell me "its ok pal" (lol) because im about to take it out of storage next week and dont want to drive it too much nor romp on it with a clogged cat. Im obsessive and insanely detailed oriented with my vehicles; to the point of neurotic. As you can probably tell
Im just looking for outside validation i guess and for someone to just tell me "its ok pal" (lol) because im about to take it out of storage next week and dont want to drive it too much nor romp on it with a clogged cat. Im obsessive and insanely detailed oriented with my vehicles; to the point of neurotic. As you can probably tell
As you have a 2000+ vehicle that is exhibiting the typical condition (code with no other driveability issues), it's most likely that you are facing the same issue that mine (and many others) did - coatings wearing off the substrate which results in increased tail pipe emissions. The reference to "efficiency below threshold" in this code definition might be misleading or concerning to some, but understand that it doesn't indicate that the cat is inefficient at flowing exhaust, just inefficient at reducing tail pipe emissions (i.e. oxygen storage capacity). There is no monitoring system or code to indicate an exhaust blockage or reduction in flow.
FWIW, you would continue to see the P0420/P0430 codes if you deleted the cats entirely (hence no possibility of blockage) but left the rear O2s in place and didn't modify the factory tune because, again, these codes are in no way a "flow monitor".
That's not to say that this code couldn't also pop up when a cat has become damaged enough to be clogged, but then you'd have other driveability issues as well (as mentioned above) and the code would still be related to an inability of the cat to meet a certain oxygen storage threshold (not anything to do with any reduction in exhaust flow - that's a separate issue for which there is no code).
04-20-2023, 01:22 PM
#24
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On my Jeep swap I used a pair of flow master cats, stainless polished and are not the typical stock waffle can,
they made the exhaust fitting much easier. If your just replacing its worth a look. Will also bump the sound up just a bit.
they made the exhaust fitting much easier. If your just replacing its worth a look. Will also bump the sound up just a bit.
04-20-2023, 01:59 PM
#25
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The code (P0420/P0430) does not directly indicate a clogged cat. In fact, there is no specific code to indicate such; a clog is something that can only be verified by removal and inspection of the cat or, if severe enough, other diagnostic options (such as IR thermometer checking for unusual heat signature, and/or other driveability issues often associated with an exhaust blockage - e.g. inability to reach high rpm, loss of power, loss of MPG, idle inconsistencies, suspicious vacuum readings).
As you have a 2000+ vehicle that is exhibiting the typical condition (code with no other driveability issues), it's most likely that you are facing the same issue that mine (and many others) did - coatings wearing off the substrate which results in increased tail pipe emissions. The reference to "efficiency below threshold" in this code definition might be misleading or concerning to some, but understand that it doesn't indicate that the cat is inefficient at flowing exhaust, just inefficient at reducing tail pipe emissions (i.e. oxygen storage capacity). There is no monitoring system or code to indicate an exhaust blockage or reduction in flow.
FWIW, you would continue to see the P0420/P0430 codes if you deleted the cats entirely (hence no possibility of blockage) but left the rear O2s in place and didn't modify the factory tune because, again, these codes are in no way a "flow monitor".
That's not to say that this code couldn't also pop up when a cat has become damaged enough to be clogged, but then you'd have other driveability issues as well (as mentioned above) and the code would still be related to an inability of the cat to meet a certain oxygen storage threshold (not anything to do with any reduction in exhaust flow - that's a separate issue for which there is no code).
As you have a 2000+ vehicle that is exhibiting the typical condition (code with no other driveability issues), it's most likely that you are facing the same issue that mine (and many others) did - coatings wearing off the substrate which results in increased tail pipe emissions. The reference to "efficiency below threshold" in this code definition might be misleading or concerning to some, but understand that it doesn't indicate that the cat is inefficient at flowing exhaust, just inefficient at reducing tail pipe emissions (i.e. oxygen storage capacity). There is no monitoring system or code to indicate an exhaust blockage or reduction in flow.
FWIW, you would continue to see the P0420/P0430 codes if you deleted the cats entirely (hence no possibility of blockage) but left the rear O2s in place and didn't modify the factory tune because, again, these codes are in no way a "flow monitor".
That's not to say that this code couldn't also pop up when a cat has become damaged enough to be clogged, but then you'd have other driveability issues as well (as mentioned above) and the code would still be related to an inability of the cat to meet a certain oxygen storage threshold (not anything to do with any reduction in exhaust flow - that's a separate issue for which there is no code).
word. I know theres no specific code to indicate a blockage. p0420 is pretty universal and just states lack of efficiency. I figure its not clogged because like i said too, i put FOUR bottles of cataclean through it in a span of 1k miles lol. And it still screams in the upper rpm range, no weird surging or bucking at low to mid rpm either as ive had before with my old once was 2001 GMC Sonoma. Fresh tune up as soon as i brought it home with 63k miles on it... Yes ive only put 2k miles on it since owning it for 4 years now lol. And yeah i will definitely not be keeping the factory tune when the cats get deleted... Thanks for the reply as well as validation.
05-15-2023, 07:17 AM
#26
word. I know theres no specific code to indicate a blockage. p0420 is pretty universal and just states lack of efficiency. I figure it’s not clogged because like i said too, i put FOUR bottles of cataclean through it in a span of 1k miles lol. And it still screams in the upper rpm range, no weird surging or bucking at low to mid rpm either as ive had before with my old once was 2001 GMC Sonoma. Fresh tune up as soon as i brought it home with 63k miles on it... Yes ive only put 2k miles on it since owning it for 4 years now lol. And yeah i will definitely not be keeping the factory tune when the cats get deleted... Thanks for the reply as well as validation.
https://ls1tech.com/forums/generatio...p0430-7-a.html