Originally Posted by j21black
Cold air intakes will throw a code on occasion. Something about the amount of air it lets through vs. the stock unit. The only way to ensure it doesn't happen is to tune the truck.
This is correct if you aren't tuned. My S&B does the same thing where sometimes it is on and sometimes it is off. When it first did it to me, I did some research. It sounds like the truck monitors the flow of air into the motor and out of the motor. The flow between the two needs to be within a certain range between the two. (I am not sure if this is how they determine when the DPF is starting to get plugged and needs to Regen, or what)
Anyways, when that ratio of air in/air out goes out of spec, you get the error code. Since the S&B flows better than a stock intake, you have already thrown that ratio off a little bit. Then as the DPF fills up, the ratio finally gets out of the acceptable range, and you get the light.
All of the posts that I could find seemed to be related to the AFE intakes and not the S&B's, but my S&B does it.
At least, that is how I understand it...