P0420 Diagnostic Trouble Code Discussion for August 2018
Catalyst Efficiency Below Normal (Bank 1)
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| Help Request | Posted | |
| 2002 Subaru Impreza Outback 2.5L MIL Lamp on VIN: JF1GG68532 P0420: Catalyst Efficiency Below Normal (Bank 1). We are about out of things to try to fix this car. We have replaced the cat with a Dealer OEM cat, replaced both front and rear 02 sensors twice. Test driving the rear o2 readings stay right around .6v they don't vary much but I would expect to see a highe... |
August 15, 2018 |
