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P0420 Diagnostic Trouble Code Discussion for October 2011

Catalyst Efficiency Below Normal (Bank 1)

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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