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P0420 Diagnostic Trouble Code Discussion for December 2011

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2007 Chevrolet Equinox LS 3.4L MIL Lamp on VIN: SCREAM1NG7
P0420: Catalyst System Low Efficiency (Bank 1). We need help with an ongoing problem with the equinox,on the last go around we replaced the rear O2 sensor.Several wierd things I dont get.Previously the data stream showed no signal fron the MAF , Air temp, or coolant temp sensor.Later they seem to working OK...
December 07, 2011
2005 Dodge Grand Caravan SXT 3.8L Stall VIN: 2D4GP44LX5
P0420: Catalyst Efficiency Below Normal (Bank 1). Customer complaint is vehicle stalls while cruising, usually only cold. He said sometimes will stall at light or when warm. No codes related to problem, we got it to stall this morning while driving at 35 mph, it acted like i let off the gas and then it stalle...
December 20, 2011
2005 Chrysler Town & Country (Van) Limited 3.8L MIL Lamp on VIN: 2C8GP64L95
P0420: Cat inefficient. Code P0420 keeps coming on/reoccuring. Cat has been replaced 2x with after market cats. O2 Sensors still mirror one another. Spoke with exhaust Repairer, the first Cat he replaced was put on a different Chrysler and NO PROBLEM with it!! Could we be this unluck...
December 28, 2011
2006 Pontiac G6 2.4L MIL Lamp on VIN: 1G2ZF55B76
P0420: Catalyst System Low Efficiency (Bank 1). Road test, runs fine. Code p0420-CAT inefficient. Watch data stream and find that cat monitor lazily hangs out around 0.8v regardless of engine speed, load, added fuel. Occasionaly the V will drop to low around 0.2. I know what a cat mon should look like after...
December 28, 2011
2006 Pontiac G6 2.4L MIL Lamp on VIN: 1G2ZF55B76
P0420: Catalyst System Low Efficiency (Bank 1). Road test, runs fine. Code p0420-CAT inefficient. Watch data stream and find that cat monitor lazily hangs out around 0.8v regardless of engine speed, load, added fuel. Occasionaly the V will drop to low around 0.2. I know what a cat mon should look like after...
December 29, 2011
2007 Chevrolet Equinox LS 3.4L MIL Lamp on VIN: SCREAM1NG7
P0420: Catalyst System Low Efficiency (Bank 1). We need help with an ongoing problem with the equinox,on the last go around we replaced the rear O2 sensor.Several wierd things I dont get.Previously the data stream showed no signal fron the MAF , Air temp, or coolant temp sensor.Later they seem to working OK...
December 07, 2011
2005 Dodge Grand Caravan SXT 3.8L Stall VIN: 2D4GP44LX5
P0420: Catalyst Efficiency Below Normal (Bank 1). Customer complaint is vehicle stalls while cruising, usually only cold. He said sometimes will stall at light or when warm. No codes related to problem, we got it to stall this morning while driving at 35 mph, it acted like i let off the gas and then it stalle...
December 20, 2011
2005 Chrysler Town & Country (Van) Limited 3.8L MIL Lamp on VIN: 2C8GP64L95
P0420: Cat inefficient. Code P0420 keeps coming on/reoccuring. Cat has been replaced 2x with after market cats. O2 Sensors still mirror one another. Spoke with exhaust Repairer, the first Cat he replaced was put on a different Chrysler and NO PROBLEM with it!! Could we be this unluck...
December 28, 2011
2006 Pontiac G6 2.4L MIL Lamp on VIN: 1G2ZF55B76
P0420: Catalyst System Low Efficiency (Bank 1). Road test, runs fine. Code p0420-CAT inefficient. Watch data stream and find that cat monitor lazily hangs out around 0.8v regardless of engine speed, load, added fuel. Occasionaly the V will drop to low around 0.2. I know what a cat mon should look like after...
December 28, 2011
2006 Pontiac G6 2.4L MIL Lamp on VIN: 1G2ZF55B76
P0420: Catalyst System Low Efficiency (Bank 1). Road test, runs fine. Code p0420-CAT inefficient. Watch data stream and find that cat monitor lazily hangs out around 0.8v regardless of engine speed, load, added fuel. Occasionaly the V will drop to low around 0.2. I know what a cat mon should look like after...
December 29, 2011