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P0420 Diagnostic Trouble Code Discussion for August 2013

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2003 Nissan Altima SE 3.5L Hesitation, Pinging VIN: 1N4BL11E13
P0420: Catalyst Efficiency Below Normal (Bank 1). ... energy. Car starts very good, idle is very good. No abnormal engine noise. But it is pinging at WOT at around 4000 RPM and it lacks power. Code P0420 was pending with the MIL lamp off. Tested cat back pressure on both banks with less than 1 PSI at idle. L...
August 05, 2013
2006 Nissan Maxima SL 3.5L MIL Lamp on VIN: 1N4BA41E66
P0420: Catalyst Efficiency Below Normal (Bank 1). ... maxima that has p0420 - bank 1 CAT. read most of the fixes talking about PCM update to widen the CAT range logic, i believe it's a tsb. do i do the update or replace the CAT? thanks guys in advance.
August 06, 2013
2001 Dodge Ram 1500 WS 3.9L MIL Lamp on VIN: 1B7HC16X01
P0420: Cat Efficiency low bank 1. ... a p0420 code I have watched the pid data and it is a mirror image switching perfectly. I think it is the best mirror image I have seen. I unpluged the rear 02 to see if scanner would pickup on the change and it did. I did a temperature test and have a temp...
August 22, 2013
2006 Ford F-150 XLT 5.4L MIL Lamp on VIN: 1FTPW14V76
P0420: Cat eff bank 1. ... on a ford after moving to a GM dealer. We have a used f150 with a 5.4 that is setting a p0420 cat eff bank 1. before it came here it went to the local ford dealer and they diagnosed the cat as being bad. Well he brought it to us for a second look. And firs...
August 26, 2013
2003 Nissan Altima SE 3.5L Hesitation, Pinging VIN: 1N4BL11E13
P0420: Catalyst Efficiency Below Normal (Bank 1). ... energy. Car starts very good, idle is very good. No abnormal engine noise. But it is pinging at WOT at around 4000 RPM and it lacks power. Code P0420 was pending with the MIL lamp off. Tested cat back pressure on both banks with less than 1 PSI at idle. L...
August 26, 2013
2006 Ford F-150 XLT 5.4L MIL Lamp on VIN: 1FTPW14V76
P0420: Cat eff bank 1. ... on a ford after moving to a GM dealer. We have a used f150 with a 5.4 that is setting a p0420 cat eff bank 1. before it came here it went to the local ford dealer and they diagnosed the cat as being bad. Well he brought it to us for a second look. And firs...
August 28, 2013