Originally Posted by Red370

your O2 sensors dont like the extra air flow, need to either one, get the sensor out of the air path i/e put an extender on the bung, or restrict what the sensors are reading, i/e steel wool stuffed into the bungs on the HFC's, the code will clear after it finishes its cycle, which seems to be 500-1000 miles, DO NOT take it into the dealer because modifying the cats is an illegal procedure and sure to kill your warranty. ESPECIALLY in texas, heres my suggestion, do what I did, throw some steel wool in the bung, clear the code, wait and see if it comes back, 99% of the time it wont.