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P0420 Diagnostic Trouble Code Discussion for May 2010

Catalyst Efficiency Below Normal (Bank 1)

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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2005 Ford F-350 Super Duty XL 5.4L No Start, Stall, Misfire VIN: 1FTWW31545
P0420: Bank 1 cat effiency below limit. This truck has left the customer stranded twice now. On Friday he drove about 100kms and it took him over 2 hours. Truck would lose throttle resonse - then die on the side of the highway. He'd wait a few minutes and then restart and go, and die and wait and go...
May 04, 2010
2004 Dodge Dakota 3.7L Poor Idle Quality, Stall, Misfire, MIL Lamp on VIN: 1D7GG16K84
P0420: Catalyst Efficiency Below Normal (Bank 1). ... techs or any tech that has had this problem before. We sold this truck Friday mourning and nothing was wrong with this truck. We got gas before it left. In the afternoon it came back in missing and the check engine light on and code P0300 in history and 1 ...
May 10, 2010
2001 Volkswagen Jetta GLS 2.8L MIL Lamp on VIN: 3VWSG69M01
P0420: catalyst system bank 1 efficiency below threshold. This is a chain drive vr6. not worried about the cat code right now. car came in from the used car lot and they said "put a cam sensor in it" we did and still have the cel tripping as soon as the car starts. Went ahead and did a little more looking. fo...
May 20, 2010
2004 Hyundai Elantra GLS 2.0L MIL Lamp on VIN: KMHDN4D34U
P0420: Catalyst Efficiency Below Normal. Why catylist is bad, although sensors are functioning normaly. Is this a common problem? I really would like to avoid putting a very $$ convertor on this. Mica
May 25, 2010