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P0420 Diagnostic Trouble Code Discussion for October 2010

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2002 Toyota Sienna LE 3.0L MIL Lamp on VIN: 4T3ZF13CX1
P0420: Catalyst Efficiency Below Normal (Bank 1). ... a flash is available for p0420 there is a bulletin on ecu update (says to replace ecu for updated logic) i do have old ecu calibration but want to know if anyone has flashed for this recently i purchased pass thru pro II but toyota says ecu must be replace...
October 07, 2010
2005 Nissan Pathfinder LE 4.0L MIL Lamp on VIN: 5N1AR18WX5
P0420: Catalyst Efficiency Below Normal (Bank 1). ... timer complaining of emission failure with a code P0420 bank one cat convertor efficiency, i look at O2 sensor values and right side O2 before cat value never goes above .30 volts, right side read normal, i switch O2 sensors before cat left to right and ri...
October 20, 2010
2005 Nissan Pathfinder LE 4.0L MIL Lamp on VIN: 5N1AR18WX5
P0420: Catalyst Efficiency Below Normal (Bank 1). ... timer complaining of emission failure with a code P0420 bank one cat convertor efficiency, i look at O2 sensor values and right side O2 before cat value never goes above .30 volts, right side read normal, i switch O2 sensors before cat left to right and ri...
October 25, 2010