CAMARO6 - View Single Post - What Codes Should Be Cleared BEFORE Installing Headers?

Spaceman · 01-31-2026, 09:39 AM

I own a '23 SS 1LE with the A10 transmission. I recently purchased the American Racing Headers long system (with cats), which will remove the AFM valves, and tie into the stock NPP muffler. I plan to do the install myself and then take it to a tuner.

If someone could please answer the following questions, I would greatly appreciate it:

1) What codes related to the O2 sensors and AFM valves need to be cleared BEFORE installing the headers?

2) Will the newest version of HP Tuners VCM Editor still allow me to access the emissions parameters?

Context:
I decided to do some digging around this forum just to see if there were any "header install gotachas" before starting the install, and sure enough, I stumbled upon the permanent code issue.

Apparently, '17-'24 year models require that you clear certain codes BEFORE installing the headers to ensure a permanent code isn't written. Based on my research, P0420 and P0430 must be set "No Error Reported," but I wanted to make sure there are no other codes that need to be cleared as well, especially since I am removing the AFM valves.

Also, based on reading forum posts and finding a video on youtube, apparently HP Tuners no longer lets you access the emissions parameters. The youtube video claims you can access them after taking a series of tests via the HP Tuners website, but I wanted to confirm that this was still an option, and they haven't taken away this capability completely. A lot of the comments on the video were having issues with process. The link to the video is below:
HPTuners Emissions Parameters Unlock How To!!

01-31-2026, 09:39 AM	#1
Spaceman Drives: 2023 Camaro SS 1LE Join Date: Nov 2023 Location: Texas Posts: 8	What Codes Should Be Cleared BEFORE Installing Headers? I own a '23 SS 1LE with the A10 transmission. I recently purchased the American Racing Headers long system (with cats), which will remove the AFM valves, and tie into the stock NPP muffler. I plan to do the install myself and then take it to a tuner. If someone could please answer the following questions, I would greatly appreciate it: 1) What codes related to the O2 sensors and AFM valves need to be cleared BEFORE installing the headers? 2) Will the newest version of HP Tuners VCM Editor still allow me to access the emissions parameters? Context: I decided to do some digging around this forum just to see if there were any "header install gotachas" before starting the install, and sure enough, I stumbled upon the permanent code issue. Apparently, '17-'24 year models require that you clear certain codes BEFORE installing the headers to ensure a permanent code isn't written. Based on my research, P0420 and P0430 must be set "No Error Reported," but I wanted to make sure there are no other codes that need to be cleared as well, especially since I am removing the AFM valves. Also, based on reading forum posts and finding a video on youtube, apparently HP Tuners no longer lets you access the emissions parameters. The youtube video claims you can access them after taking a series of tests via the HP Tuners website, but I wanted to confirm that this was still an option, and they haven't taken away this capability completely. A lot of the comments on the video were having issues with process. The link to the video is below: HPTuners Emissions Parameters Unlock How To!! Last edited by Spaceman; 01-31-2026 at 09:56 AM.