P0430 Code after reverting tune to stock?

[str8himalaya]

Hi all!

I recently bought a 2012 Camaro SS that came with a spectre CAI and a vararam power wedge installed. The guy that had it before me had it tuned and it was burpling all over the place and felt like the idle and drive rpm’s were cranked up to the point it lunged a bit coming off the brake. I reverted everything to stock last night and drove around for a solid 45 minutes. Right before heading home the check engine line popped on throwing a P0430 “catalyst system efficiency below threshold bank 2” code. After a little research it appears it could be the cat on the passenger side or the o2 sensor. The question I have is, will it throw this code if it’s not tuned properly? I never had it throw the code driving it recently, albeit I never drove it for as long as I did last night. Sorry for the long post, but curious on the thoughts to address. I was planning to go with long tubes this summer at some point anyways.

[Joe.G]

A CAI should not cause this code, there is a chance that the other tune was rich and screwed up the cats, You can hook a scanner up and watch the O2 sensors and see if they are working correctly. If you are not able to then I would try to replace the 02 sensors ( all 4 ). If you are going to LTH soon with either no cats or Hi Flo cats ( I recommend the cats I think it sounds better ) then this code should be taken care of as the rear sensors will be de tuned or shut off. I would still run New )2 with the headers as the fronts are still important.

[ZL1_Chris]

Wondering since you are saying you are straight piped do you still have cats and is there still downstream o2s. Its possible the previous tune had the downstream o2s disabled. If you do have cats and the previous owner had a verbal tune installed your cats are probably melted.

[str8himalaya]

Originally Posted by Joe.G

A CAI should not cause this code, there is a chance that the other tune was rich and screwed up the cats, You can hook a scanner up and watch the O2 sensors and see if they are working correctly. If you are not able to then I would try to replace the 02 sensors ( all 4 ). If you are going to LTH soon with either no cats or Hi Flo cats ( I recommend the cats I think it sounds better ) then this code should be taken care of as the rear sensors will be de tuned or shut off. I would still run New )2 with the headers as the fronts are still important.

Wouldn’t surprise me at all if the cats were toast. The guy had the thing running super rich because he liked the popping sound. I was hopeful it wasn’t going to toast the cats but it may have, which isn’t a surprise. I was planning on going with some high flow cats anyways with the LTH setup so it can probably wait until then. I can hook my tuner up and see what the cats are saying, at least I think I can do that with a SCT x4 tuner.

[Joe.G]

If you are not sure how to do it, watch a you tube video. If it was really rich I'd assume cats are probably shot. Not a big deal if replacing them anyway.

[1JEWLDSSRS]

Originally Posted by str8himalaya

Wouldn’t surprise me at all if the cats were toast. The guy had the thing running super rich because he liked the popping sound. I was hopeful it wasn’t going to toast the cats but it may have, which isn’t a surprise. I was planning on going with some high flow cats anyways with the LTH setup so it can probably wait until then. I can hook my tuner up and see what the cats are saying, at least I think I can do that with a SCT x4 tuner.

IIRC, from what I've read on here over the years, the snapping, popping, crackling sound is not from him having the car running rich, it is caused by the DFCO, (deceleration fuel cutoff). When you take your foot of the throttle and decelerate, the ECU shuts down the injectors so there isn't and excess fuel introduced into the chambers. Hence the popping and crackling sound. Since you are straight piped, you will here it really good, and any after market performance mufflers will allow you to hear it better as well. This program, (DFCO) can be tuned to be off in the fuel system program, but is advised against for the reasons that too much fuel in the combustion chamber on idle and deceleration would "wash" the cylinder walls of oil and cause problems, and run rich to boot. Just not a good thing. Hope this explains a little for you, and if it isn't right, someone will chime in Im sure. But yes, on the cat deal, if they had it running rich, they will most likely be toast as stated already!!

[InFiD3ViL]

Originally Posted by 1JEWLDSSRS

IIRC, from what I've read on here over the years, the snapping, popping, crackling sound is not from him having the car running rich, it is caused by the DFCO, (deceleration fuel cutoff). When you take your foot of the throttle and decelerate, the ECU shuts down the injectors so there isn't and excess fuel introduced into the chambers. Hence the popping and crackling sound. Since you are straight piped, you will here it really good, and any after market performance mufflers will allow you to hear it better as well. This program, (DFCO) can be tuned to be off in the fuel system program, but is advised against for the reasons that too much fuel in the combustion chamber on idle and deceleration would "wash" the cylinder walls of oil and cause problems, and run rich to boot. Just not a good thing. Hope this explains a little for you, and if it isn't right, someone will chime in Im sure. But yes, on the cat deal, if they had it running rich, they will most likely be toast as stated already!!

That's exactly how it is usually done on our cars. In addition to what you mentioned, it is not exactly the best thing for the health of your valves and guides as well, since the continuous popping and backfiring puts added stress on them.

[str8himalaya]

Originally Posted by 1JEWLDSSRS

IIRC, from what I've read on here over the years, the snapping, popping, crackling sound is not from him having the car running rich, it is caused by the DFCO, (deceleration fuel cutoff). When you take your foot of the throttle and decelerate, the ECU shuts down the injectors so there isn't and excess fuel introduced into the chambers. Hence the popping and crackling sound. Since you are straight piped, you will here it really good, and any after market performance mufflers will allow you to hear it better as well. This program, (DFCO) can be tuned to be off in the fuel system program, but is advised against for the reasons that too much fuel in the combustion chamber on idle and deceleration would "wash" the cylinder walls of oil and cause problems, and run rich to boot. Just not a good thing. Hope this explains a little for you, and if it isn't right, someone will chime in Im sure. But yes, on the cat deal, if they had it running rich, they will most likely be toast as stated already!!

That's great information, thank you! I have been messing around with the settings in the tuner and so far after resetting the code I haven't seen it pop up since. Might have been the computer figuring things back out after resetting, who knows. I planned on going with some headers at some point in the relatively near future so might be a moot point anyways. Just making sure it wasn't something critical that couldn't wait for a fix, sounds like it's probably alright for a little while. It's not my daily driver, more of my fun weekend car I want to build up a bit.

[1JEWLDSSRS]

Originally Posted by str8himalaya

That's great information, thank you! I have been messing around with the settings in the tuner and so far after resetting the code I haven't seen it pop up since. Might have been the computer figuring things back out after resetting, who knows. I planned on going with some headers at some point in the relatively near future so might be a moot point anyways. Just making sure it wasn't something critical that couldn't wait for a fix, sounds like it's probably alright for a little while. It's not my daily driver, more of my fun weekend car I want to build up a bit.

Yes sir, you're welcome. Enjoy!!