I'm on the verge of trading in my car over this god damn code. Short of tuning it out I've tried everything. The code btw is P0420.

 

for sharing. Is there a question you have for us?

 

http://www.evoxforums.com/forums/showthread.php?t=34136

 

Or try this thread
https://www.evolutionm.net/forums/ev...0420-code.html
Google my friend works wonders

 

So, have you removed, modded or other wise replaced the cat? If so put the stock one back on. If you havent and its a stock cat-- replace it with another one, either from the forum or aftermarket-- like magnaflow OEM cats.. dont be thinking the sparkplug extenders or other bs is going to be a permanent fix, sometimes they work, sometime not and if you did anything with the rear o2, put it back. That goes for HFC ( hi flow) cat-- .