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P0420 Diagnostic Trouble Code Discussion for December 2008

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
1998 Chevrolet Metro 1.0L MIL Lamp on VIN: 2C1MR2269W
P0420: cat. efficiency below threshold. ... came in w/ck. eng. light on. p0420 cat. code. Cat. has been replaced sometime in the past. Checking o2 readings w/ scantool, I find hos2 voltage @1.25v. unchanging. I'm not sure what diagnostic to use for that. Please wake me up. Thank you
December 06, 2008
1998 Chevrolet Metro 1.0L MIL Lamp on VIN: 2C1MR2269W
P0420: cat. efficiency below threshold. ... came in w/ck. eng. light on. p0420 cat. code. Cat. has been replaced sometime in the past. Checking o2 readings w/ scantool, I find hos2 voltage @1.25v. unchanging. I'm not sure what diagnostic to use for that. Please wake me up. Thank you
December 08, 2008
1996 Subaru Legacy L 2.2L MIL Lamp on
P0420: Catalyst Efficiency Below Normal (Bank 1). Hello fellow techs, my question is about catalytic converters. This vehicle has california emmisions. I need to replace the catalytic converter. My question is will the oem federal emmision cat work on this vehicle? Will it pass all the moniters? Or do I have ...
December 18, 2008