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P0420 Diagnostic Trouble Code Discussion for April 2009

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2005 Subaru Impreza WRX 2.0L MIL Lamp on VIN: JF4GG22645
P0420: Catalyst Efficiency Below Normal (Bank 1). replace cat with factory for po420,code returned in less than 1000 miles-i suspect the front air fuel ratio sensor may be the problem-but cant find a spec for its output voltage, thanks for your help.
April 02, 2009
2002 Volkswagen Jetta GLS 2.0L MIL Lamp on VIN: 3VWSK69M82
P0420: catalyst system efficiency below threshold bank 1. ... engine light on. code #16804 (p0420) catalyst system efficiency below threshold, bank 1. this car has had the converter replaced by volkswagen in june of 2007. there are no other codes. the tune up componants are new & the car has a new bosch rear 02 s...
April 03, 2009
2005 Nissan Altima S 2.5L MIL Lamp on VIN: 1N4AL11D85
P0420: Catalyst Efficiency Below Normal (Bank 1). ... 2.5 ltr engine and it keeps setting p0420. The cat has been changed twice both are aftermarket the a/f ratio sensor was changed we called nissan and was told the computer update was done. Any help would be greatly appricated Thanks Tony
April 14, 2009
2006 Nissan Titan XE 5.6L Hesitation, Stall, bogs/lacks power VIN: 1N6BA07AX6
P0420: Three-Way Catalyst Malfunction (Bank 1). Hello again Iatn, I have this Titan and it is driving me crazy. 2 weeks ago it came in and presented with the classic bogs on accel, lack of power, stalling under load with accompanying catalyst efficiency codes. It was just recently tuned (plugs) at the deale...
April 15, 2009
2006 Nissan Titan XE 5.6L Hesitation, Stall, bogs/lacks power VIN: 1N6BA07AX6
P0420: Three-Way Catalyst Malfunction (Bank 1). Hello again Iatn, I have this Titan and it is driving me crazy. 2 weeks ago it came in and presented with the classic bogs on accel, lack of power, stalling under load with accompanying catalyst efficiency codes. It was just recently tuned (plugs) at the deale...
April 16, 2009
1997 Toyota Avalon XL 3.0L MIL Lamp on VIN: 4T1BF1ZB6V
P0420: Catalyst Efficiency Below Normal (Bank 1). vehicle came in with mil lite on. we scanned and found code for egr position sensor, we tested mand replaced sensor, code fixed. vehicle came back with codes po420 , inefficient cat, and code po135 b1s1 circuit problem. we scoped all 3 sensors , rear sensor is...
April 20, 2009
2003 Toyota Corolla CE 1.8L MIL Lamp on VIN: 1NXBR32E33
P0420: Catalyst Efficiency Below Normal (Bank 1). This car appears to be covered under the EG028-04 TSB calling for a cat #17410-0D360 and a reflash.The cal.id. is [...]-which shows to be the "new i.d." #. Local dealer says the VIN does not bring up that TSB and that I need a 17410-0D150 cat.Am I misr...
April 24, 2009
2004 Volkswagen Jetta GLS 1.8L MIL Lamp on VIN: 3VWSE69M94
P0420: cat sys eff below threshold. Hi and thanks in advance for any and all responses. Reall just a question for the VW techs out there. This Jetta had the above codes and the b2s2 had flat lined at .005v when we pulled the 4 wire connector apart under the vehicle the cavity was full of a very ...
April 24, 2009
1996 Chevrolet Blazer 4.3L Hesitation, Cuts out VIN: 1GNCT18W4T
P0420: Catalyst System Low Efficiency (Bank 1). Good customer, good thing! I haven't given up on this but I would like to! Breif history...Last fall, towed in, no fuel-replace pump and wire harness to pump, towed in again in January, removed 1+ gallons of water!(vehicle vandalized). We replaced pump, flushe...
April 27, 2009
2005 Subaru Impreza WRX 2.0L MIL Lamp on VIN: JF4GG22645
P0420: Catalyst Efficiency Below Normal (Bank 1). replace cat with factory for po420,code returned in less than 1000 miles-i suspect the front air fuel ratio sensor may be the problem-but cant find a spec for its output voltage, thanks for your help.
April 27, 2009
2004 Volkswagen Jetta GLS 1.8L MIL Lamp on VIN: 3VWSE69M94
P0420: cat sys eff below threshold. Hi and thanks in advance for any and all responses. Reall just a question for the VW techs out there. This Jetta had the above codes and the b2s2 had flat lined at .005v when we pulled the 4 wire connector apart under the vehicle the cavity was full of a very ...
April 27, 2009
2004 Ford Taurus SE 3.0L MIL Lamp on VIN: 1FAFP53U34
P0420: Catlyst low efficiency bank 1. ... some spark knock on accel. History is minimal and only have car for 3 days. Oil consumpsion is normal. Customer had car for about 45 days before code set, no repairs or events to blame it on. Some times takes a week, last time was next day and light came o...
April 28, 2009
1996 Chevrolet Blazer 4.3L Hesitation, Cuts out VIN: 1GNCT18W4T
P0420: Catalyst System Low Efficiency (Bank 1). Good customer, good thing! I haven't given up on this but I would like to! Breif history...Last fall, towed in, no fuel-replace pump and wire harness to pump, towed in again in January, removed 1+ gallons of water!(vehicle vandalized). We replaced pump, flushe...
April 29, 2009
2004 Ford Taurus SE 3.0L MIL Lamp on VIN: 1FAFP53U34
P0420: Catlyst low efficiency bank 1. ... some spark knock on accel. History is minimal and only have car for 3 days. Oil consumpsion is normal. Customer had car for about 45 days before code set, no repairs or events to blame it on. Some times takes a week, last time was next day and light came o...
April 30, 2009
1997 Toyota Avalon XL 3.0L MIL Lamp on VIN: 4T1BF1ZB6V
P0420: Catalyst Efficiency Below Normal (Bank 1). vehicle came in with mil lite on. we scanned and found code for egr position sensor, we tested mand replaced sensor, code fixed. vehicle came back with codes po420 , inefficient cat, and code po135 b1s1 circuit problem. we scoped all 3 sensors , rear sensor is...
April 30, 2009
2005 Subaru Impreza WRX 2.0L MIL Lamp on VIN: JF4GG22645
P0420: Catalyst Efficiency Below Normal (Bank 1). replace cat with factory for po420,code returned in less than 1000 miles-i suspect the front air fuel ratio sensor may be the problem-but cant find a spec for its output voltage, thanks for your help.
April 02, 2009
2002 Volkswagen Jetta GLS 2.0L MIL Lamp on VIN: 3VWSK69M82
P0420: catalyst system efficiency below threshold bank 1. ... engine light on. code #16804 (p0420) catalyst system efficiency below threshold, bank 1. this car has had the converter replaced by volkswagen in june of 2007. there are no other codes. the tune up componants are new & the car has a new bosch rear 02 s...
April 03, 2009
2005 Nissan Altima S 2.5L MIL Lamp on VIN: 1N4AL11D85
P0420: Catalyst Efficiency Below Normal (Bank 1). ... 2.5 ltr engine and it keeps setting p0420. The cat has been changed twice both are aftermarket the a/f ratio sensor was changed we called nissan and was told the computer update was done. Any help would be greatly appricated Thanks Tony
April 14, 2009
2006 Nissan Titan XE 5.6L Hesitation, Stall, bogs/lacks power VIN: 1N6BA07AX6
P0420: Three-Way Catalyst Malfunction (Bank 1). Hello again Iatn, I have this Titan and it is driving me crazy. 2 weeks ago it came in and presented with the classic bogs on accel, lack of power, stalling under load with accompanying catalyst efficiency codes. It was just recently tuned (plugs) at the deale...
April 15, 2009
2006 Nissan Titan XE 5.6L Hesitation, Stall, bogs/lacks power VIN: 1N6BA07AX6
P0420: Three-Way Catalyst Malfunction (Bank 1). Hello again Iatn, I have this Titan and it is driving me crazy. 2 weeks ago it came in and presented with the classic bogs on accel, lack of power, stalling under load with accompanying catalyst efficiency codes. It was just recently tuned (plugs) at the deale...
April 16, 2009
1997 Toyota Avalon XL 3.0L MIL Lamp on VIN: 4T1BF1ZB6V
P0420: Catalyst Efficiency Below Normal (Bank 1). vehicle came in with mil lite on. we scanned and found code for egr position sensor, we tested mand replaced sensor, code fixed. vehicle came back with codes po420 , inefficient cat, and code po135 b1s1 circuit problem. we scoped all 3 sensors , rear sensor is...
April 20, 2009
2003 Toyota Corolla CE 1.8L MIL Lamp on VIN: 1NXBR32E33
P0420: Catalyst Efficiency Below Normal (Bank 1). This car appears to be covered under the EG028-04 TSB calling for a cat #17410-0D360 and a reflash.The cal.id. is [...]-which shows to be the "new i.d." #. Local dealer says the VIN does not bring up that TSB and that I need a 17410-0D150 cat.Am I misr...
April 24, 2009
2004 Volkswagen Jetta GLS 1.8L MIL Lamp on VIN: 3VWSE69M94
P0420: cat sys eff below threshold. Hi and thanks in advance for any and all responses. Reall just a question for the VW techs out there. This Jetta had the above codes and the b2s2 had flat lined at .005v when we pulled the 4 wire connector apart under the vehicle the cavity was full of a very ...
April 24, 2009
1996 Chevrolet Blazer 4.3L Hesitation, Cuts out VIN: 1GNCT18W4T
P0420: Catalyst System Low Efficiency (Bank 1). Good customer, good thing! I haven't given up on this but I would like to! Breif history...Last fall, towed in, no fuel-replace pump and wire harness to pump, towed in again in January, removed 1+ gallons of water!(vehicle vandalized). We replaced pump, flushe...
April 27, 2009
2005 Subaru Impreza WRX 2.0L MIL Lamp on VIN: JF4GG22645
P0420: Catalyst Efficiency Below Normal (Bank 1). replace cat with factory for po420,code returned in less than 1000 miles-i suspect the front air fuel ratio sensor may be the problem-but cant find a spec for its output voltage, thanks for your help.
April 27, 2009
2004 Volkswagen Jetta GLS 1.8L MIL Lamp on VIN: 3VWSE69M94
P0420: cat sys eff below threshold. Hi and thanks in advance for any and all responses. Reall just a question for the VW techs out there. This Jetta had the above codes and the b2s2 had flat lined at .005v when we pulled the 4 wire connector apart under the vehicle the cavity was full of a very ...
April 27, 2009
2004 Ford Taurus SE 3.0L MIL Lamp on VIN: 1FAFP53U34
P0420: Catlyst low efficiency bank 1. ... some spark knock on accel. History is minimal and only have car for 3 days. Oil consumpsion is normal. Customer had car for about 45 days before code set, no repairs or events to blame it on. Some times takes a week, last time was next day and light came o...
April 28, 2009
1996 Chevrolet Blazer 4.3L Hesitation, Cuts out VIN: 1GNCT18W4T
P0420: Catalyst System Low Efficiency (Bank 1). Good customer, good thing! I haven't given up on this but I would like to! Breif history...Last fall, towed in, no fuel-replace pump and wire harness to pump, towed in again in January, removed 1+ gallons of water!(vehicle vandalized). We replaced pump, flushe...
April 29, 2009
2004 Ford Taurus SE 3.0L MIL Lamp on VIN: 1FAFP53U34
P0420: Catlyst low efficiency bank 1. ... some spark knock on accel. History is minimal and only have car for 3 days. Oil consumpsion is normal. Customer had car for about 45 days before code set, no repairs or events to blame it on. Some times takes a week, last time was next day and light came o...
April 30, 2009
1997 Toyota Avalon XL 3.0L MIL Lamp on VIN: 4T1BF1ZB6V
P0420: Catalyst Efficiency Below Normal (Bank 1). vehicle came in with mil lite on. we scanned and found code for egr position sensor, we tested mand replaced sensor, code fixed. vehicle came back with codes po420 , inefficient cat, and code po135 b1s1 circuit problem. we scoped all 3 sensors , rear sensor is...
April 30, 2009