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P0420 Diagnostic Trouble Code Discussion for December 2012

Catalyst Efficiency Below Normal (Bank 1)

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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
1999 Honda CR-V LX 2.0L MIL Lamp on VIN: JHLRD1849X
P0420: Catalyst Efficiency Below Threshold (Bank 1). I have this cr-v thats being a night mare. I have a p1457 code. Yes i have read all the tsb's and they dont apply. I started with a smoke test and found a hole in tank. Replaced gas tank resmoked tested system found no leaks. 2 days later its back with just th...
December 05, 2012
2005 Dodge Ram 1500 ST 5.7L MIL Lamp on VIN: 1D7HU18D65
P0420: Cat converter bank one. I can tell Cat code is not a Cat problem it is a problem with fuel control on number one cylinder. Was going into open loop on bank one and no switches on bank one upstream O2 which is normal in open loop. Bank two is in closed loop front O2 switching fine. Sw...
December 09, 2012
2001 Buick Century Limited 3.1L Excessive Emissions, Poor Idle Quality, Hesitation, Cuts out, Misfire VIN: 2G4WY55J51
P0420: Catalyst System Low Efficiency. this car idles bad and when you try to accelerate it back fires pops and falls flat, the cat converter was completly melted down. i checked data with snap on scanner all seemed ok except st and lt were in neg at idle maf was at 13 grms per sec which i thought ...
December 11, 2012
2006 Volkswagen Golf GL 2.0L Cuts out, Stall, MIL Lamp on VIN: 9BWFL61J66
P0420: catalyst efficiency low bank 1. Here's one for all of you to ponder over the Christmas weekend. I have this VW with a phantom stalling problem. Unfortunately I don't have much to go on, as the problem has not once occured for me. In addition, it like pulling teeth to get info out of the cust...
December 21, 2012