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P0420 Diagnostic Trouble Code Discussion for January 2010

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2006 Subaru Legacy 2.5i 2.5L MIL Lamp on VIN: 4S3BP62666
P0420: Catalyst Efficiency Below Normal (Bank 1). ... I have a p0420 code which appears to be the cat. but my cruise light is also flashing and I have not seen this before. If anyone can enlighten me on why my cruise light is flashing it would be greatly appreciated. thank you.
January 04, 2010
2002 Ford Crown Victoria Police Interceptor 4.6L Poor Idle Quality, Misfire, MIL Lamp on VIN: 2FAFP71W02
P0420: cat code. ... gear. will set a p0301 code, and both cat codes. fuel trims at idle long term (bank 1) -12 to -19 and (bank 2) is +20. both o2 react to added fuel and induced vac leaks, however if egr is opened only bank 1 reacts? there are...
January 06, 2010
2002 Subaru Outback 2.5L MIL Lamp on VIN: 4S3BH67562
P0420: Catalyst Efficiency Below Normal (Bank 1). PO420 returns after driving vehicle approx 100 miles. Downsteam o2 voltage fluctuates indicating cat not working. No exhaust leaks or other codes,datastream looks normal
January 08, 2010
2001 Nissan Maxima GLE 3.0L Stall, MIL Lamp on VIN: JN1CA31D81
P0420: Catalyst Efficiency Below Normal (Bank 1). hello fellow techs. thanks for reading this post. your help will be appreciated. this maxima was towed in with main complaint of heavy electrical smell and a/c not working. found alternator charging at 17 volts and specific gravity of battery fluid, charcoal i...
January 19, 2010
2001 Nissan Maxima GLE 3.0L Stall, MIL Lamp on VIN: JN1CA31D81
P0420: Catalyst Efficiency Below Normal (Bank 1). hello fellow techs. thanks for reading this post. your help will be appreciated. this maxima was towed in with main complaint of heavy electrical smell and a/c not working. found alternator charging at 17 volts and specific gravity of battery fluid, charcoal i...
January 21, 2010
1999 Chevrolet Tahoe LS 5.7L MIL Lamp on VIN: 3GNEK18RXG
P0420: Catalyst System Low Efficiency (Bank 1). Looking for suggestions on my personal truck, I would like to install an electric cooling fan in my truck but dont want to spend $400 for a kit from Jegs. I dont want to have to have a toggle switch to turn the fan on either. Please let me know if anyone has d...
January 22, 2010
2001 Nissan Maxima GLE 3.0L MIL Lamp on VIN: JN1CA31111
P0420: Catalyst Efficiency Below Normal (Bank 1). Ok this Maxima has a P0420 and i know its the catalityc. Heres the catch. The 2 Downsteam O2's are not reading at all. So I did the DMM test and read the B+ grn signal but no return signal on both so I replace the O2's. New O2's installed the same thing. So I ...
January 25, 2010
2006 Nissan Maxima SE 3.5L MIL Lamp on VIN: 1N4BA41E86
P0420: Catalyst Efficiency Below Normal (Bank 1). ... years. retrieved code p2a03- o2 sensor range/ performance. found fuse number 15 in underdash fuse panel had been removed. installed new fuse. cleared cel. cel came back on with p0420- cat efficency. inspected cats with boros...
January 28, 2010
2007 Toyota Prius 1.5L MIL Lamp on VIN: JTDKB20U67
P0420: catalyst system efficiency below threshold bank 1. HELLO. WE ARE WORKING ON 2007 TOYOTA PRIUS THAT CAME IN WITH A CHECK ENGINE CODE #PO420.(CAT SYSTEM EFFICIENCY BELOW THRESHOLD (BANK 1). WE ARE TRYING TO MAKE SURE WE ARE COVERING ALL OUR BASES BEFORE WE CONDEMN THE CAT(S),SINCE THESE ARE EXPENSIVE JEWELS AND ...
January 28, 2010
2006 Nissan Maxima SE 3.5L MIL Lamp on VIN: 1N4BA41E86
P0420: Catalyst Efficiency Below Normal (Bank 1). ... years. retrieved code p2a03- o2 sensor range/ performance. found fuse number 15 in underdash fuse panel had been removed. installed new fuse. cleared cel. cel came back on with p0420- cat efficency. inspected cats with boros...
January 29, 2010
2006 Subaru Legacy 2.5i 2.5L MIL Lamp on VIN: 4S3BP62666
P0420: Catalyst Efficiency Below Normal (Bank 1). ... I have a p0420 code which appears to be the cat. but my cruise light is also flashing and I have not seen this before. If anyone can enlighten me on why my cruise light is flashing it would be greatly appreciated. thank you.
January 04, 2010
2002 Ford Crown Victoria Police Interceptor 4.6L Poor Idle Quality, Misfire, MIL Lamp on VIN: 2FAFP71W02
P0420: cat code. ... gear. will set a p0301 code, and both cat codes. fuel trims at idle long term (bank 1) -12 to -19 and (bank 2) is +20. both o2 react to added fuel and induced vac leaks, however if egr is opened only bank 1 reacts? there are...
January 06, 2010
2002 Subaru Outback 2.5L MIL Lamp on VIN: 4S3BH67562
P0420: Catalyst Efficiency Below Normal (Bank 1). PO420 returns after driving vehicle approx 100 miles. Downsteam o2 voltage fluctuates indicating cat not working. No exhaust leaks or other codes,datastream looks normal
January 08, 2010
2001 Nissan Maxima GLE 3.0L Stall, MIL Lamp on VIN: JN1CA31D81
P0420: Catalyst Efficiency Below Normal (Bank 1). hello fellow techs. thanks for reading this post. your help will be appreciated. this maxima was towed in with main complaint of heavy electrical smell and a/c not working. found alternator charging at 17 volts and specific gravity of battery fluid, charcoal i...
January 19, 2010
2001 Nissan Maxima GLE 3.0L Stall, MIL Lamp on VIN: JN1CA31D81
P0420: Catalyst Efficiency Below Normal (Bank 1). hello fellow techs. thanks for reading this post. your help will be appreciated. this maxima was towed in with main complaint of heavy electrical smell and a/c not working. found alternator charging at 17 volts and specific gravity of battery fluid, charcoal i...
January 21, 2010
1999 Chevrolet Tahoe LS 5.7L MIL Lamp on VIN: 3GNEK18RXG
P0420: Catalyst System Low Efficiency (Bank 1). Looking for suggestions on my personal truck, I would like to install an electric cooling fan in my truck but dont want to spend $400 for a kit from Jegs. I dont want to have to have a toggle switch to turn the fan on either. Please let me know if anyone has d...
January 22, 2010
2001 Nissan Maxima GLE 3.0L MIL Lamp on VIN: JN1CA31111
P0420: Catalyst Efficiency Below Normal (Bank 1). Ok this Maxima has a P0420 and i know its the catalityc. Heres the catch. The 2 Downsteam O2's are not reading at all. So I did the DMM test and read the B+ grn signal but no return signal on both so I replace the O2's. New O2's installed the same thing. So I ...
January 25, 2010
2006 Nissan Maxima SE 3.5L MIL Lamp on VIN: 1N4BA41E86
P0420: Catalyst Efficiency Below Normal (Bank 1). ... years. retrieved code p2a03- o2 sensor range/ performance. found fuse number 15 in underdash fuse panel had been removed. installed new fuse. cleared cel. cel came back on with p0420- cat efficency. inspected cats with boros...
January 28, 2010
2007 Toyota Prius 1.5L MIL Lamp on VIN: JTDKB20U67
P0420: catalyst system efficiency below threshold bank 1. HELLO. WE ARE WORKING ON 2007 TOYOTA PRIUS THAT CAME IN WITH A CHECK ENGINE CODE #PO420.(CAT SYSTEM EFFICIENCY BELOW THRESHOLD (BANK 1). WE ARE TRYING TO MAKE SURE WE ARE COVERING ALL OUR BASES BEFORE WE CONDEMN THE CAT(S),SINCE THESE ARE EXPENSIVE JEWELS AND ...
January 28, 2010
2006 Nissan Maxima SE 3.5L MIL Lamp on VIN: 1N4BA41E86
P0420: Catalyst Efficiency Below Normal (Bank 1). ... years. retrieved code p2a03- o2 sensor range/ performance. found fuse number 15 in underdash fuse panel had been removed. installed new fuse. cleared cel. cel came back on with p0420- cat efficency. inspected cats with boros...
January 29, 2010