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P0420 Diagnostic Trouble Code Discussion for January 2013

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2005 Honda Pilot EX 3.5L Excessive Emissions, MIL Lamp on VIN: 2HKYF18415
P0420: Catalyst Efficiency Below Threshold (Bank 1). ... CEL and stalling and no start a couple of times after timing belt job just done. Of course it everything was fine during my test drive after I initially completed the job... Scanned and found P0340 only. Inspected and found water in the CMP sensor connecto...
January 21, 2013
2005 Honda Pilot EX 3.5L Excessive Emissions, MIL Lamp on VIN: 2HKYF18415
P0420: Catalyst Efficiency Below Threshold (Bank 1). ... CEL and stalling and no start a couple of times after timing belt job just done. Of course it everything was fine during my test drive after I initially completed the job... Scanned and found P0340 only. Inspected and found water in the CMP sensor connecto...
January 21, 2013
2004 Cadillac SRX 4.6L Misfire, MIL Lamp on VIN: 1GYEE63A94
P0420: Catalyst System Low Efficiency (Bank 1). please help car has been back a few times we replaced the engine sometime in nov 29, car keeps coming back to our shop with different codes everytime we replaced engine, throttle body assy., coils, injectors,plugs
January 22, 2013
2005 Honda Pilot EX 3.5L Excessive Emissions, MIL Lamp on VIN: 2HKYF18415
P0420: Catalyst Efficiency Below Threshold (Bank 1). ... CEL and stalling and no start a couple of times after timing belt job just done. Of course it everything was fine during my test drive after I initially completed the job... Scanned and found P0340 only. Inspected and found water in the CMP sensor connecto...
January 21, 2013
2005 Honda Pilot EX 3.5L Excessive Emissions, MIL Lamp on VIN: 2HKYF18415
P0420: Catalyst Efficiency Below Threshold (Bank 1). ... CEL and stalling and no start a couple of times after timing belt job just done. Of course it everything was fine during my test drive after I initially completed the job... Scanned and found P0340 only. Inspected and found water in the CMP sensor connecto...
January 21, 2013
2004 Cadillac SRX 4.6L Misfire, MIL Lamp on VIN: 1GYEE63A94
P0420: Catalyst System Low Efficiency (Bank 1). please help car has been back a few times we replaced the engine sometime in nov 29, car keeps coming back to our shop with different codes everytime we replaced engine, throttle body assy., coils, injectors,plugs
January 22, 2013