I have Art Pipes, typically there's zero issues with a CEL, the only exception is on a long road trip and I get on it to accelerate to freeway speeds and only once, never happened on two separate occasions on the same trip. Usually P1147. Then I can clear the code and it doesn't come back. Doesn't do this every road trip, maybe every 2nd or 3rd one. So it really isn't a serious issue and in day to day driving it has never happened. Just more curious as to what triggers it under those specific conditions.