P0420 Diagnostic Trouble Code Discussion for August 2019
Catalyst Efficiency Below Normal (Bank 1)
Note: This is a professional automotive technician's resource.
Vehicle Owners: If you are seeking an automotive repair professional to service your vehicle, visit the iATN Repair Shop Finder.Trouble Ticket Help Requests for DTC P0420
| Help Request | Posted | |
| 2007 Subaru Outback 2.5i Basic 2.5L MIL Lamp on VIN: 4S4BP61CX7 P0420: Catalyst Efficiency Below Normal (Bank 1). ... Subaru Outback and keep getting a P0420. Vehicle was in a couple weeks ago with the same code. I replaced the front A/F ratio sensor and thought it fixed the problem. Yesterday the vehicle came back with the MIL on and same P0420. LTFT was at -12 to-13... |
August 15, 2019 |
