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P0420 Diagnostic Trouble Code Discussion for April 2012

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2003 Toyota RAV4 2.0L Excessive Emissions, Misfire, MIL Lamp on VIN: JTEHH20V03
P0420: Catalyst Efficiency Below Normal (Bank 2). Vehicle keeps going through ignition coils had first set of coils from standard ignition Others replaced at another shop from Napa Auto Parts. As a result of being driven with the misfire it has destroyed two catalytic convertors. Cant find the reason for the ...
April 03, 2012
2001 Toyota Corolla CE 1.8L Excessive Emissions, Poor Idle Quality, Hesitation, MIL Lamp on VIN: 2T1BR12E11
P0420: Catalyst Efficiency Below Normal (Bank 1). ... Has been in with the same reoccurring problem. Setting codes P0171 and P0420. The MAF has been replaced with a toyota part. The cat was replaced with 2 aftermarket normal emissions cats, then a california emissions aftermarket cat. The o2 sensors were also...
April 05, 2012
2001 Toyota Corolla CE 1.8L Excessive Emissions, Poor Idle Quality, Hesitation, MIL Lamp on VIN: 2T1BR12E11
P0420: Catalyst Efficiency Below Normal (Bank 1). ... Has been in with the same reoccurring problem. Setting codes P0171 and P0420. The MAF has been replaced with a toyota part. The cat was replaced with 2 aftermarket normal emissions cats, then a california emissions aftermarket cat. The o2 sensors were also...
April 09, 2012
2000 Porsche 911 Carrera 3.4L MIL Lamp on VIN: WP0CA2997Y
P0420: Catalytic converter efficiency bank 1. customer brought car in a couple of weeks ago. read the diagnostics. (same 2 codes present) cleared the codes. sent him on his way. light returned with same code. my question is, is this a common problem? is it typically the sensor. and if so, has anyone repla...
April 17, 2012
2002 Nissan Altima 2.5L Excessive Emissions, Hesitation, Surge, Stall VIN: 1N4AL11DX2
P0420: Catalyst Efficiency Below Normal (Bank 1). ... regular customer that we do all the work on this car. We put an engine & converter in it about 8 months ago for the usual oil burning problems these cars had. They have since put over 10,000 miles on the car. This problem is probably not related to tha...
April 20, 2012
2001 Volkswagen Jetta GLS 2.0L Hesitation VIN: 3VWSK69M51
P0420: cat efficiency bank 1. good afternoon all,thank you in advance for any and all help,vehicle was brought in last night with a lack of power complaint,test drove car,car ran great,above codes were stored,replaced ign coil(cracked housing) and wires(misfire when watered down)this morni...
April 25, 2012
2003 Toyota RAV4 2.0L Excessive Emissions, Misfire, MIL Lamp on VIN: JTEHH20V03
P0420: Catalyst Efficiency Below Normal (Bank 2). Vehicle keeps going through ignition coils had first set of coils from standard ignition Others replaced at another shop from Napa Auto Parts. As a result of being driven with the misfire it has destroyed two catalytic convertors. Cant find the reason for the ...
April 03, 2012
2001 Toyota Corolla CE 1.8L Excessive Emissions, Poor Idle Quality, Hesitation, MIL Lamp on VIN: 2T1BR12E11
P0420: Catalyst Efficiency Below Normal (Bank 1). ... Has been in with the same reoccurring problem. Setting codes P0171 and P0420. The MAF has been replaced with a toyota part. The cat was replaced with 2 aftermarket normal emissions cats, then a california emissions aftermarket cat. The o2 sensors were also...
April 05, 2012
2001 Toyota Corolla CE 1.8L Excessive Emissions, Poor Idle Quality, Hesitation, MIL Lamp on VIN: 2T1BR12E11
P0420: Catalyst Efficiency Below Normal (Bank 1). ... Has been in with the same reoccurring problem. Setting codes P0171 and P0420. The MAF has been replaced with a toyota part. The cat was replaced with 2 aftermarket normal emissions cats, then a california emissions aftermarket cat. The o2 sensors were also...
April 09, 2012
2000 Porsche 911 Carrera 3.4L MIL Lamp on VIN: WP0CA2997Y
P0420: Catalytic converter efficiency bank 1. customer brought car in a couple of weeks ago. read the diagnostics. (same 2 codes present) cleared the codes. sent him on his way. light returned with same code. my question is, is this a common problem? is it typically the sensor. and if so, has anyone repla...
April 17, 2012
2002 Nissan Altima 2.5L Excessive Emissions, Hesitation, Surge, Stall VIN: 1N4AL11DX2
P0420: Catalyst Efficiency Below Normal (Bank 1). ... regular customer that we do all the work on this car. We put an engine & converter in it about 8 months ago for the usual oil burning problems these cars had. They have since put over 10,000 miles on the car. This problem is probably not related to tha...
April 20, 2012
2001 Volkswagen Jetta GLS 2.0L Hesitation VIN: 3VWSK69M51
P0420: cat efficiency bank 1. good afternoon all,thank you in advance for any and all help,vehicle was brought in last night with a lack of power complaint,test drove car,car ran great,above codes were stored,replaced ign coil(cracked housing) and wires(misfire when watered down)this morni...
April 25, 2012