Sorry this isn't addressed to me...but I TOTALLY feel your pain about Illinois emissions, quite irritating...I'll be keeping my car registered in Florida for at least a year while I live in Illinois!
But it really shouldn't throw any codes if it's installed right, similar to the way an S-AFC wont throw codes unless something is connected wrong...or if you choose to remove your downstream O2 sensors (also known as Code 27 - Sub Heated O2)
But it really shouldn't throw any codes if it's installed right, similar to the way an S-AFC wont throw codes unless something is connected wrong...or if you choose to remove your downstream O2 sensors (also known as Code 27 - Sub Heated O2)