**************All this info is borrowed from EPhatch.com***********************
Available at your local automotive store. Spark Plug Non Fouler PN 42009 ($4.99)
You now need to drill out 1 of the non foulers using a 1/2" drill bit. When finished this is what it will look like.
Side by Side comparision of the orignal and now modified non foulers
o2 Sensor inserted in the modified non fouler
Second, unmodified non fouler now installed on modified non fouler
Original non fouler->Modified non fouler->o2 sensor
Fully installed
By moving the secondary o2 sensor away from the direct path of exhaust flow and limiting what exhaust gas can get to the o2 sensor the ecu believes that there is a functioning cat still in the system.
I personally used this on my EP3. It worked for 1,000 miles then i sold all the parts and put her back to stock. I am not sure what other Civics this will work on but i am assuming it will work on any OBD2 cars. but for 5 bucks its worth a try.
This was posted primarly for dank24.