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P0420 Diagnostic Trouble Code Discussion for June 2007

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2002 Lexus IS300 3.0L MIL Lamp on VIN: JTHBD19222
P0420: Catalyst Efficiency Below Normal (Bank 1). .To all valued techs this car came in for catt efficiency po420 bank 1 checked basics because before we address cats we found LT 1 & LT 2 POS 38% ST bothe at around 7 % obvous lean condition this is at idle comes down just a little at cruise .did complete ...
June 06, 2007
2002 Lexus IS300 3.0L MIL Lamp on VIN: JTHBD19222
P0420: Catalyst Efficiency Below Normal (Bank 1). .To all valued techs this car came in for catt efficiency po420 bank 1 checked basics because before we address cats we found LT 1 & LT 2 POS 38% ST bothe at around 7 % obvous lean condition this is at idle comes down just a little at cruise .did complete ...
June 12, 2007
2002 Pontiac Grand Am GT 3.4L Lack of power VIN: 1G2NV52E82
P0420: Catalyst System Low Efficiency. This car came to me a week ago. Customer complained of lack of power. There was no check engine light on at this time. Went to the fuel filter and changed it, "black" fuel came out. Changed the filter added a cleaner and told the customer to see if tha...
June 26, 2007
1997 Chevrolet Lumina 3.1L No Start, Poor Idle Quality, Misfire VIN: 2G1WL52M7V
P0420: Catalyst System Low Efficiency. This car came to me on a hook. Customer stated that on his way down the highway, he experienced a couple of "bucks" acting like a misfire. It eventually lost power and stalled out. After it sat here for a few days till I could look at it, it started ve...
June 27, 2007
2002 Pontiac Grand Am GT 3.4L Lack of power VIN: 1G2NV52E82
P0420: Catalyst System Low Efficiency. This car came to me a week ago. Customer complained of lack of power. There was no check engine light on at this time. Went to the fuel filter and changed it, "black" fuel came out. Changed the filter added a cleaner and told the customer to see if tha...
June 27, 2007
2001 Volvo S60 2.4L MIL Lamp on VIN: YV1RS61N81
P0420: cat inefficent. keep getting code p0420 after driving cat temps nearly same at front and back but scan data while driving shows both o2 sensors nearly flat line with very little movement. Alldata's info for p0420 check for air leaks replace injectors if no results replace cat...
June 28, 2007
2002 Lexus IS300 3.0L MIL Lamp on VIN: JTHBD19222
P0420: Catalyst Efficiency Below Normal (Bank 1). .To all valued techs this car came in for catt efficiency po420 bank 1 checked basics because before we address cats we found LT 1 & LT 2 POS 38% ST bothe at around 7 % obvous lean condition this is at idle comes down just a little at cruise .did complete ...
June 06, 2007
2002 Lexus IS300 3.0L MIL Lamp on VIN: JTHBD19222
P0420: Catalyst Efficiency Below Normal (Bank 1). .To all valued techs this car came in for catt efficiency po420 bank 1 checked basics because before we address cats we found LT 1 & LT 2 POS 38% ST bothe at around 7 % obvous lean condition this is at idle comes down just a little at cruise .did complete ...
June 12, 2007
2002 Pontiac Grand Am GT 3.4L Lack of power VIN: 1G2NV52E82
P0420: Catalyst System Low Efficiency. This car came to me a week ago. Customer complained of lack of power. There was no check engine light on at this time. Went to the fuel filter and changed it, "black" fuel came out. Changed the filter added a cleaner and told the customer to see if tha...
June 26, 2007
1997 Chevrolet Lumina 3.1L No Start, Poor Idle Quality, Misfire VIN: 2G1WL52M7V
P0420: Catalyst System Low Efficiency. This car came to me on a hook. Customer stated that on his way down the highway, he experienced a couple of "bucks" acting like a misfire. It eventually lost power and stalled out. After it sat here for a few days till I could look at it, it started ve...
June 27, 2007
2002 Pontiac Grand Am GT 3.4L Lack of power VIN: 1G2NV52E82
P0420: Catalyst System Low Efficiency. This car came to me a week ago. Customer complained of lack of power. There was no check engine light on at this time. Went to the fuel filter and changed it, "black" fuel came out. Changed the filter added a cleaner and told the customer to see if tha...
June 27, 2007
2001 Volvo S60 2.4L MIL Lamp on VIN: YV1RS61N81
P0420: cat inefficent. keep getting code p0420 after driving cat temps nearly same at front and back but scan data while driving shows both o2 sensors nearly flat line with very little movement. Alldata's info for p0420 check for air leaks replace injectors if no results replace cat...
June 28, 2007