Spark Plug Non Fouler PN 42009 ($4.99)
Available from your local automotive store:
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 comparison of the original and now modified non fouler
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
The idea behind it is when you remove the cat the 2nd o2 sensor is going to have too much crap reaching the sensor that isnít filtered out, which will make it think the cat has gone bad. What this does is it moves the o2 sensor further away so a limited amount of exhaust gets to the o2 sensor, it is a VERY little amount that actually gets to the sensor but as long as it is considerably less than the primary o2 sensor then it wonít cause a