2000 Subaru Outback "po420 catalyst efficiency below threshold" Questions

...PO420 CATALYST SYSTEM EFFICIENCY BELOW THRESHOLD BANK I * CODE PO325 KNOCK SENSOR NO.1 CIRCUIT MALFUNCTION BANK NO.1 OR SINGLE SENSOR P0325 Knock Sensor Circuit Malfunction P0420 Catalyst System ...

not help. The code PO420 you have is Catalyst System efficiency is below threshold bank one. Usually replacing the O2 sensor that's the front most in the exhaust system will cure your problem,. Thanks

...PO420 is for catalyst system efficiency below threshold. I have seen this many times on vehicles from 96 up. It is due to the system not burning the fuel at what it considers an acceptable rate. ...

...PO420 catalyst efficiency below threshold There is a code PO420 catalyst below threshold now appearing with the engine light on. We have the plugs replaced when misfire code came. Then we had cables ...

...po420 po306 for mercury cougar 1999 P0430 code is(catalyst efficiency below threshold on bank 2)P0420 code is((catalyst efficiency below threshold on bank 1)P0306 code is(cylinder 6 misfire

...po420=catalyst system efficiency below threshold bank #1 code po430=catalyst system efficiency below threshold bank #2 from autozone online ...

...PO420: Catalyst System Efficiency Below Threshold (Bank 1) PO421: Warm-Up Catalyst Efficiency Below Threshold (Bank 1) PO430: Catalyst System Efficiency Below Threshold (Bank 2) PO431: Warm-Up ...

po420 left bank catalyst failure the muffeler shop said it was ok but the light remains on Catalyst System Efficiency Below Threshold Bank 1, Is telling you that the drivers side converter is not ...

...PO420: Catalyst System Efficiency Below Threshold (Bank 1) PO421: Warm-Up Catalyst Efficiency Below Threshold (Bank 1) PO430: Catalyst System Efficiency Below Threshold (Bank 2) PO431: Warm-Up ...

...PO420 Catalyst System Efficiency below threshold. what do i need to do to get this fixed? is it expensive? can part be picked up from junkyard? can problem get fixed with avoiding mechanics? need ...