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P0420 Diagnostic Trouble Code Discussion for September 2009

Catalyst Efficiency Below Normal (Bank 1)

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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2003 Dodge Ram 1500 SLT 5.7L o2s votlage VIN: 1D7HU18D53
P0420: catylst efficiency. o2 sensors 1 and 2 remain around 3.5 volts constant after replacing both sensors
September 02, 2009
2000 Toyota Sienna CE 3.0L MIL Lamp on
P0420: Catalyst Efficiency Below Normal (Bank 1). can not get rid of code po420 kees coming back catylast below effciency replaced o2 sensors and coverta from engine to muffler all o2 sensors c/o in parameters i do not have a way to check the waves
September 03, 2009
2003 Toyota RAV4 2.0L MIL Lamp on VIN: JTEHH20V43
P0420: Catalyst Efficiency Below Normal (Bank 2). Vehicle requires repair for state inspection and I don't want to replace the cat and find out there is some other problem triggering these codes. I am suspicious because the diagnostic information in Alldata - supposedly right from Toyota - mentions that the A...
September 04, 2009
2006 Dodge Charger SXT 3.5L Stall, MIL Lamp on VIN: 2B3KA46G56
P0420: Catalyst Efficiency Below Normal (Bank 1). ... time officer states car stalls at idle and at highway speeds it allways restart vehicle has not duplicated the symtom while in the shop but has come in twice with the same codes pending codes are po42o and p0430 freeze frame po174 engine run 48min 45 sec t...
September 15, 2009
2002 Volkswagen Jetta GLS 2.0L MIL Lamp on VIN: 3VWSK69M32
P0420: Cat Efficiency. Not sure what's happening with this one. First it's a VW and I haven't worked on many of these. After scanning the computer and finding the 420 code, I looked at some of the scan data which is limited because I only had generic mode on my Brick. The data showe...
September 24, 2009