lancelot1

2015 c7, highly modified, 800 rwhp. Last month I had the Corsa axle back installed and it triggered aCEL. The code P26c8.
I took it to my tuner he did what he thought would fix it but it did not. Onstar sends me a diagnostic summary each month and
they do not see an issue. Called Corsa they were not much help. Car runs fine. Hate to have to take it to a dealer. Looking for
any help I can get. Thanks.

CP

Did you remove the AFM valves? If so, that will throw a code.

rrsperry

Sure looks like a AFM code.

bbrown450

That would be the logical conclusion with that limited mod..

lancelot1

Your right, Corsa does say this could happen but what is the solution? My tuner could not resolve it. I can delete the code but it always returns.

Akcajunz

I believe I read a post on here once stating that when you remove the AFM valves, there is a module that you connect into the wire harness to fool the computer into thinking the valves are still there...resulting in no CEL. I'll keep looking for it and see if I can find it again. Good Luck!

62RPO582

I found this. I don't know if it's what you are talking about.
https://www.shopmrt.com/GM-AFM-NPP-P...0-p/91x010.htm

lakemg

There's a thread somewhere on the forum that discuss how to tune out the code...

Akcajunz

I'm still looking, but no, thats not what I was referring to...what I remember was a module that plugs into the wire harness where the AFM valve plugs in. The member said it fools the computer into thinking the valves are plugged in therefore no CEL. It's been a couple years since I read it.

62RPO582

Your not thinking of the range device are you?

Akcajunz

Nope, I'm pretty sure it was not the Range device, I have one of those in my Stingray. I gave up looking for the thread, I tried every key word I could think of. From what I remember, it was a small module that plugged into the harness, not the OBDII port under the dash. And he zip tied the connection out of the way. Sorry that I cant locate the thread.

mrclean1

If you eliminated the AFM valves, that is what is throwing the code. If they are still there, one or both are not functioning and is causing the code.

eboggs_jkvl

Didn't the guy just wrap up the AFM valves in some heat shield material, zip tied the pair up and out of the way and left the valves just hang still in the system?


Elmer

jaywoo

Here ya go. Easy to do with hp tuners.

https://www.corvetteforum.com/forums...hp-tuners.html

yaknow

I believe this is what your looking for

https://www.corvetteforum.com/forums...te-module.html

ran across this earlier in the week when trying to determine what to do with my afm valves. For $30 I may try MRT product before shelling out $350 for a tune

phils C5 vette

This is what you have to do. Your tuner will have to license the valve to turn off.