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P0420 Diagnostic Trouble Code Discussion for August 2006

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
1996 Subaru Legacy Outback 2.5L MIL Lamp on VIN: 4S3BG6851T
P0420: Catalyst Efficiency Below Normal (Bank 1). ... this one. car came to me from another shop that could not fix. scanned codes and found p0420 catalyst eff. below threshold bank 1. now at the previous shop they installed new o2 sensors and the front converter. i really dont know where to start, not much i...
August 07, 2006
1999 Acura TL 3.2L Misfire, MIL Lamp on VIN: 19UUA5648X
P0420: Catalyst Efficiency Below Threshold (Bank 1). Hello, Car came in with ck engine light on as well as TCS light, car runs poorly with obvious misfire occuring at all times. Besides above mentioned codes, the remaining cylinder misfire codes are set, and reset in a short test drive (less than 5 miles) as w...
August 09, 2006
1996 Subaru Legacy Outback 2.5L MIL Lamp on VIN: 4S3BG6851T
P0420: Catalyst Efficiency Below Normal (Bank 1). ... this one. car came to me from another shop that could not fix. scanned codes and found p0420 catalyst eff. below threshold bank 1. now at the previous shop they installed new o2 sensors and the front converter. i really dont know where to start, not much i...
August 09, 2006
2003 Suzuki Vitara 2.0L Hesitation, Cuts out, Stall, Misfire VIN: 2S3TE52V73
P0420: Catalyst Efficiency Below Normal (Bank 1). ... cylinder, after it gets hot it will some time cut out and die, it will restart after a few minutes and run fine. It always starts back up before we can run many test such as fuel pressure, spark etc. THe only code it has is a p0420 for cat efficiency but i...
August 11, 2006
1997 BMW 740i 4.4L Surge, MIL Lamp on VIN: WBAGF8327V
P0420: catalyst code bank 1. Downstream and upstream o2 sensors seem to switch at the the same rate on both banks but only bank one code for cat efficiency returns. mil illumination coincides with a slight surge feeling,(reported by cust) Any help would be welcome.
August 14, 2006
2002 Subaru Impreza TS 2.5L Poor Fuel Economy, MIL Lamp on VIN: JF1GG65502
P0420: Catalyst Efficiency Below Normal (Bank 1). everything is telling me that the air/ fuel sensor isn't working. Can not locate data to verify. Would love alldata to actually tell me how to test some things instead of just replace. Can someone out there Please tell me more info on this system. It would be ...
August 25, 2006
2001 Volkswagen Jetta Wolfsburg Edition 1.8L MIL Lamp on VIN: 3VWPD69M71
P0420: TWC at threshhold. Hey Gang, This "People's Car" is alienating me from the "FahrVergnuegen" crowd...this and many other VWs are helping me understand why people are buying Hondas and such. Look at the repair history and you will notice that I enjoyed more than ...
August 26, 2006
1996 Subaru Legacy Outback 2.5L MIL Lamp on VIN: 4S3BG6851T
P0420: Catalyst Efficiency Below Normal (Bank 1). ... this one. car came to me from another shop that could not fix. scanned codes and found p0420 catalyst eff. below threshold bank 1. now at the previous shop they installed new o2 sensors and the front converter. i really dont know where to start, not much i...
August 07, 2006
1999 Acura TL 3.2L Misfire, MIL Lamp on VIN: 19UUA5648X
P0420: Catalyst Efficiency Below Threshold (Bank 1). Hello, Car came in with ck engine light on as well as TCS light, car runs poorly with obvious misfire occuring at all times. Besides above mentioned codes, the remaining cylinder misfire codes are set, and reset in a short test drive (less than 5 miles) as w...
August 09, 2006
1996 Subaru Legacy Outback 2.5L MIL Lamp on VIN: 4S3BG6851T
P0420: Catalyst Efficiency Below Normal (Bank 1). ... this one. car came to me from another shop that could not fix. scanned codes and found p0420 catalyst eff. below threshold bank 1. now at the previous shop they installed new o2 sensors and the front converter. i really dont know where to start, not much i...
August 09, 2006
2003 Suzuki Vitara 2.0L Hesitation, Cuts out, Stall, Misfire VIN: 2S3TE52V73
P0420: Catalyst Efficiency Below Normal (Bank 1). ... cylinder, after it gets hot it will some time cut out and die, it will restart after a few minutes and run fine. It always starts back up before we can run many test such as fuel pressure, spark etc. THe only code it has is a p0420 for cat efficiency but i...
August 11, 2006
1997 BMW 740i 4.4L Surge, MIL Lamp on VIN: WBAGF8327V
P0420: catalyst code bank 1. Downstream and upstream o2 sensors seem to switch at the the same rate on both banks but only bank one code for cat efficiency returns. mil illumination coincides with a slight surge feeling,(reported by cust) Any help would be welcome.
August 14, 2006
2002 Subaru Impreza TS 2.5L Poor Fuel Economy, MIL Lamp on VIN: JF1GG65502
P0420: Catalyst Efficiency Below Normal (Bank 1). everything is telling me that the air/ fuel sensor isn't working. Can not locate data to verify. Would love alldata to actually tell me how to test some things instead of just replace. Can someone out there Please tell me more info on this system. It would be ...
August 25, 2006
2001 Volkswagen Jetta Wolfsburg Edition 1.8L MIL Lamp on VIN: 3VWPD69M71
P0420: TWC at threshhold. Hey Gang, This "People's Car" is alienating me from the "FahrVergnuegen" crowd...this and many other VWs are helping me understand why people are buying Hondas and such. Look at the repair history and you will notice that I enjoyed more than ...
August 26, 2006