2000 Subaru Outback "sensor change po420 code" Questions

...MALFUNCTION BANK NO.1 OR SINGLE SENSOR P0325 Knock Sensor Circuit Malfunction P0420 Catalyst System Efficiency Below Threshold I would change the knock sensor first and the other may clear up

After changing the egr and the tube, something else is causing the restriction. a more thorough diagnosis is recommended. The po420 code sounds like a possible catalyst failure or an o2 sensor failure

...PO420. catalys system below efficieny. My father's 99 Suburban had a similar code for Bank 2(passenger side).Change the O2 sensors before and after the catalytic converter for the driver's ...

...the little computer up to your car and they can clear out the code as well. change the o2 sensor where the catalyst converter is .if my info was of any help to you please leave a comment

...2 error codes po420 bank 1 and po430 bank 2 error codes caused a failed inspection sounds like O2 sensors to me. I havent changed one on a mustang yet but I havent had any trouble with any others ...

...CHANGE SENSOR That code refers to oxygen sensors ahead and behind catalytic converter, reading is too similar. Not sure from your posting whether you replaced one in front, and one behind catalytic ...

po420. The catalitic converter was changed an still got the same problem.Can anybody help? Not just a faulty catalytic converter will trigger this code. Many other issues can trigger this code. Leaded

1. Either the 02 sensor down by the cat on bank 1 is malfunctioning, or the cat converter needs replacing. Cheaper to change the 02 sensor first, then the if the problem is still there, the cat is bad

PO420. But i would check the oxygen sensor out first that also will cause a check engine light .A cheap one can fail but to check yours take it out and heat the end with a torch with and check it with

...PO420 and now when exiting the freeway the car turns off.... have to put it in park to restart and its fine, this has happened like 5 times already???Pleeease help? i really need info as to exactly ...