i failed the carbon monoxide part of e-check. what are some causes for this?? i passed last year. and all i have done is an engine swap and put a glass pack on my exhaust. are there any ways to fix this fairly easy???
thanks

 

An engine swap is a major part of determing how you will do in smog. Sorry that I can't help at all.

Chances are that you are not going to pass with a high-flo cat. Lots of them are cat looking test pipes.

 

Is this a joke? An engine swap will change everything!