04 NB Mazdaspeed issues
 

Hello everyone,


Been having check engine light on with code P0420 for couple of months and just replaced a new 2nd o2 sensor at a shop. The light came back on, I took it back to the shop and I was told the reason is no reading on that new sensor, need to tear the interior down to check the wire. I bought this vehicle a year ago, no issues with driving dynamic/power. 2004 with 20k mileage.


Bought sensor from rockauto.com, the part itself is fine after test. The vehicle is at the shop now, I will ask and update if there is new code after replacing o2 sensor.


Wondering if anyone experienced similar issue, and whats my best solution here.


Thank you!