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P0420 Diagnostic Trouble Code Discussion for February 2007

Catalyst Efficiency Below Normal (Bank 1)

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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2000 Honda Civic DX 1.6L MIL Lamp on VIN: 2HGEJ6618Y
P0420: Catalyst Efficiency Below Threshold (Bank 1). ... help. I have this Civic acustomer brought in because intermittently the car will stall while going down the freeway. But also every 2500-3000 miles the code P0420 pop's up, and each time they've had the catalyctic convertor replaced with a Honda part. When...
February 01, 2007
2001 Buick Century Custom 3.1L MIL Lamp on VIN: 2G4WS52J01
P0420: Catalyst System Low Efficiency. ... came in with bad miss fire, replace plugs and wires, unknown how long condition had been happening, approx six months ago came in with lack of power, diagnosed plugged convertor, replaced convertor with economy aftermarket, check engine light came on appro...
February 15, 2007
2001 Nissan Pathfinder LE 3.5L MIL Lamp on VIN: JN8DR09X41
P0420: Catalyst Efficiency Below Normal (Bank 1). ... little direction. the p0420 code appears to have a couple of tsb's available, the signals on the front and rear o2's look as though the cat could be starting to deteriorate, is this a common trouble or should i send them the dealer to see if the tsb's appl...
February 19, 2007
2004 Subaru Outback 2.5L MIL Lamp on VIN: 4S3BH67554
P0420: Catalyst Efficiency Below Normal (Bank 1). Cel still coming on, code P0420. No other codes. We have replaced cat convertor with dealer cat. Convertor was previously replaced in 2005 at 70k miles. We also replaced 3 O2 sensors. Engine runs fine. Vehicle is driven about 300 freeway miles daily. We have c...
February 19, 2007