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P0420 Diagnostic Trouble Code Discussion for February 2014

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2004 Isuzu Rodeo S 3.5L Poor Idle Quality, Hesitation, MIL Lamp on VIN: 4S2CK58Y44
P0420: Catalyst Efficiency Below Normal (Bank 1). The fuel trims (adding both LT and ST to get actual) on this thing are 7 on one bank and -7 on the other. I thought that plastic clogging one bank of injectors was causing this since I saw a few examples of this, and have removed and checked it, even blew it o...
February 12, 2014
2004 Isuzu Rodeo S 3.5L Poor Idle Quality, Hesitation, MIL Lamp on VIN: 4S2CK58Y44
P0420: Catalyst Efficiency Below Normal (Bank 1). The fuel trims (adding both LT and ST to get actual) on this thing are 7 on one bank and -7 on the other. I thought that plastic clogging one bank of injectors was causing this since I saw a few examples of this, and have removed and checked it, even blew it o...
February 14, 2014
2011 Dodge Durango Crew 3.6L Misfire VIN: 1D4RE4GG3B
P0420: cat efficiency bank 1. Truck misfires intermittently; but has never been felt by me. Current ramped coils and injectors all looks good. customer took it to Chrysler and they told him he needs a head. Was wondering has anyone run in to this? Or any other common causes? Are heads a co...
February 27, 2014
2004 Isuzu Rodeo S 3.5L Poor Idle Quality, Hesitation, MIL Lamp on VIN: 4S2CK58Y44
P0420: Catalyst Efficiency Below Normal (Bank 1). The fuel trims (adding both LT and ST to get actual) on this thing are 7 on one bank and -7 on the other. I thought that plastic clogging one bank of injectors was causing this since I saw a few examples of this, and have removed and checked it, even blew it o...
February 12, 2014
2004 Isuzu Rodeo S 3.5L Poor Idle Quality, Hesitation, MIL Lamp on VIN: 4S2CK58Y44
P0420: Catalyst Efficiency Below Normal (Bank 1). The fuel trims (adding both LT and ST to get actual) on this thing are 7 on one bank and -7 on the other. I thought that plastic clogging one bank of injectors was causing this since I saw a few examples of this, and have removed and checked it, even blew it o...
February 14, 2014
2011 Dodge Durango Crew 3.6L Misfire VIN: 1D4RE4GG3B
P0420: cat efficiency bank 1. Truck misfires intermittently; but has never been felt by me. Current ramped coils and injectors all looks good. customer took it to Chrysler and they told him he needs a head. Was wondering has anyone run in to this? Or any other common causes? Are heads a co...
February 27, 2014
2004 Isuzu Rodeo S 3.5L Poor Idle Quality, Hesitation, MIL Lamp on VIN: 4S2CK58Y44
P0420: Catalyst Efficiency Below Normal (Bank 1). The fuel trims (adding both LT and ST to get actual) on this thing are 7 on one bank and -7 on the other. I thought that plastic clogging one bank of injectors was causing this since I saw a few examples of this, and have removed and checked it, even blew it o...
February 12, 2014
2004 Isuzu Rodeo S 3.5L Poor Idle Quality, Hesitation, MIL Lamp on VIN: 4S2CK58Y44
P0420: Catalyst Efficiency Below Normal (Bank 1). The fuel trims (adding both LT and ST to get actual) on this thing are 7 on one bank and -7 on the other. I thought that plastic clogging one bank of injectors was causing this since I saw a few examples of this, and have removed and checked it, even blew it o...
February 14, 2014
2011 Dodge Durango Crew 3.6L Misfire VIN: 1D4RE4GG3B
P0420: cat efficiency bank 1. Truck misfires intermittently; but has never been felt by me. Current ramped coils and injectors all looks good. customer took it to Chrysler and they told him he needs a head. Was wondering has anyone run in to this? Or any other common causes? Are heads a co...
February 27, 2014
2004 Isuzu Rodeo S 3.5L Poor Idle Quality, Hesitation, MIL Lamp on VIN: 4S2CK58Y44
P0420: Catalyst Efficiency Below Normal (Bank 1). The fuel trims (adding both LT and ST to get actual) on this thing are 7 on one bank and -7 on the other. I thought that plastic clogging one bank of injectors was causing this since I saw a few examples of this, and have removed and checked it, even blew it o...
February 12, 2014
2004 Isuzu Rodeo S 3.5L Poor Idle Quality, Hesitation, MIL Lamp on VIN: 4S2CK58Y44
P0420: Catalyst Efficiency Below Normal (Bank 1). The fuel trims (adding both LT and ST to get actual) on this thing are 7 on one bank and -7 on the other. I thought that plastic clogging one bank of injectors was causing this since I saw a few examples of this, and have removed and checked it, even blew it o...
February 14, 2014
2011 Dodge Durango Crew 3.6L Misfire VIN: 1D4RE4GG3B
P0420: cat efficiency bank 1. Truck misfires intermittently; but has never been felt by me. Current ramped coils and injectors all looks good. customer took it to Chrysler and they told him he needs a head. Was wondering has anyone run in to this? Or any other common causes? Are heads a co...
February 27, 2014
2004 Isuzu Rodeo S 3.5L Poor Idle Quality, Hesitation, MIL Lamp on VIN: 4S2CK58Y44
P0420: Catalyst Efficiency Below Normal (Bank 1). The fuel trims (adding both LT and ST to get actual) on this thing are 7 on one bank and -7 on the other. I thought that plastic clogging one bank of injectors was causing this since I saw a few examples of this, and have removed and checked it, even blew it o...
February 12, 2014
2004 Isuzu Rodeo S 3.5L Poor Idle Quality, Hesitation, MIL Lamp on VIN: 4S2CK58Y44
P0420: Catalyst Efficiency Below Normal (Bank 1). The fuel trims (adding both LT and ST to get actual) on this thing are 7 on one bank and -7 on the other. I thought that plastic clogging one bank of injectors was causing this since I saw a few examples of this, and have removed and checked it, even blew it o...
February 14, 2014
2011 Dodge Durango Crew 3.6L Misfire VIN: 1D4RE4GG3B
P0420: cat efficiency bank 1. Truck misfires intermittently; but has never been felt by me. Current ramped coils and injectors all looks good. customer took it to Chrysler and they told him he needs a head. Was wondering has anyone run in to this? Or any other common causes? Are heads a co...
February 27, 2014