I just recently installed header (4-1 ss dc sport) and cat (smsp) everything was fine for a couple of weeks, but then the ecu code for the catalyst system came on, and my exhuast smells a little funny. anyone have any experience with this problem? or recommand what i should do? i dont wanna take it back to the dealers because they are probably gonna make me put my stocks on. THANKS in advance

 

I had the same problem as you did, after a week of having my new cat placed in, the 67 code came on. my problem was that I must of had an air leak somewhere between my header and exhaust cuz after a couple hard wrench tightening and resetting my ECU, everything was cool. try it out