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P0420 Diagnostic Trouble Code Discussion for November 2007

Catalyst Efficiency Below Normal (Bank 1)

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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
1998 Chrysler Concorde LX 2.7L No Start, Poor Idle Quality VIN: 2C3HD46R0W
P0420: Catalyst Efficiency Below Normal (Bank 1). customer came in complaining of hard starting and extended crank and after start up would run rough for a little while. we install new fuel pump and egr valve. customer drove for several days and the problem came back. we have good fuel preasure and cam and cr...
November 08, 2007
2000 Volvo S40 1.9L MIL Lamp on VIN: W1VS2555YF
P0420: Catalyst Efficiency. We don't see many Volvos here and after reading over the tests listed for the code P0014, I am wondering what are the most common causes. I have removed the variable valve timing control valve to check for sludge or restriction in the oil passageways and I hav...
November 08, 2007
2001 Toyota Camry CE 2.2L MIL Lamp on
P0420: Catalyst Efficiency Below Normal (Bank 1). Car came in with po420. Have seen this hundreds of times and Cat is always the culpert. Not the case this time, Replaced cat with Factory part, problem came back immediatley on Test drive after 2 trip. Checked A/F sensor and rear O2, both working properly, rep...
November 12, 2007
2003 Toyota Camry SE 2.4L MIL Lamp on VIN: 4T1BG32K23
P0420: Catalyst Efficiency Below Normal (Bank 1). Car is storing a [...] cam sensor and p0420 cat below threshold. I was able to see the cat fail on a long testdrive but the cam sensor code is a mystery. Cam sensor was replaced 5 months ago for this code and did not reset until now,and the code stored several...
November 13, 2007
2002 Oldsmobile Alero GX 2.2L MIL Lamp on VIN: 1G3NK52F72
P0420: Catalyst System Low Efficiency. ... kind of late. p0420 had above listed parts prior to this visit checked fuel press. 59psi. smoke tested clean. checked vac. 22/23in map 8 to 10 at idle. no noise from timmig chain. grafed both o2s on modis they almost look the same. i would think bad cat fr...
November 21, 2007