i had a 02 s2k and was using the invidia test pipe non resonated one, put about 30k on it and no CEL at all. So you are saying the 06-07 are more prone to CEL when using a test pipe? has anyone tried fooling the ecu electronically?

 

ok sorry for the wait... I did reset it and the CEL still came on. So I took the CEL fix off thinkking its too long and I put the Autoparts spark plug non fouler one which is shorter and the light still came on. Now I am going to take one of the autoparts fouler off to be even closer (The autoparts has 2 small pieces which you screw together) to the pipe to see what happens. I did notice that where the O2 bung is welded on to the test pipe there's a minor leak as if they forgot to weld it. Its pin size but nonetheless still leaks. Maybe that could be the problem. Let see what happens.. oh by the way I have an 04'