[5 Speed]

The P0420 might be a loose connection in the exhaust inbetween the cats. Here is a little information. I have been throwing this code for 4 years and I know it isn't the cat. because I have had two smogs tests and the smog tests are perfect. I have a scan gauge and just reset it on the move and then 4-6 months later it throws the code and I just reset it. In fact it threw the code twice on the end of a long downhill one year apart! How interesting is that! Now it might be the O2 sensor after the cat is getting old because I have 134K and it is the original sensor and as long as I can reset the code I am not going to change the sensor. It does not change the closed loupe, it is just a sensor. I have the california V-6 and the first sensor pre cat is a more expensive air-fuel ratio sensor and this is needed to run closed loupe so when it went out I replaced it.