Join Now
International Automotive Technicians Network

P0420 Diagnostic Trouble Code Discussion for October 2011

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
2000 Mazda Protege ES 1.8L Hesitation, Cuts out VIN: JM1BJ2233Y
P0420: Catalyst Efficiency Below Normal (Bank 1). ... my brothers car and I could use a little help. it hesitates and falls on its face after a hot soak. you attemp to take off and it just falls on its face and then takes off normal. it has set the p0420 code 3 times in the last 4 months. the cats do not ratt...
October 04, 2011
2007 Subaru Outback 2.5i Basic 2.5L MIL Lamp on VIN: 4S4BP61C27
P0420: Catalyst Efficiency Below Normal (Bank 1). ... check engine light on code P0420 - no exhaust leaks found. I wanted to check front O2 operation I have a Snap On Solus Pro and the voltage reading idling hot are 2.78 - 2.89 mild fluctuation the rear O2 acts more like what Iam used to seeing - 0.115 - 0.88...
October 18, 2011
2000 Mazda Protege ES 1.8L Hesitation, Cuts out VIN: JM1BJ2233Y
P0420: Catalyst Efficiency Below Normal (Bank 1). ... my brothers car and I could use a little help. it hesitates and falls on its face after a hot soak. you attemp to take off and it just falls on its face and then takes off normal. it has set the p0420 code 3 times in the last 4 months. the cats do not ratt...
October 04, 2011
2007 Subaru Outback 2.5i Basic 2.5L MIL Lamp on VIN: 4S4BP61C27
P0420: Catalyst Efficiency Below Normal (Bank 1). ... check engine light on code P0420 - no exhaust leaks found. I wanted to check front O2 operation I have a Snap On Solus Pro and the voltage reading idling hot are 2.78 - 2.89 mild fluctuation the rear O2 acts more like what Iam used to seeing - 0.115 - 0.88...
October 18, 2011