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P0420 Diagnostic Trouble Code Discussion for November 2012

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2005 Dodge Grand Caravan SXT 3.8L MIL Lamp on VIN: 2D8GP44L85
P0420: Catalyst Efficiency Below Normal (Bank 1). Van came in with mil light P 420 checked for O2 switch rate front to back, My genisys, is reading 2.49 volts for a couple seconds and then flashes to -2.51 volts continually, does the same with new sensor,It also, does this weather the van is running or not an...
November 23, 2012
1999 Oldsmobile Aurora 4.0L MIL Lamp on VIN: 1G3GR62C0X
P0420: Catalyst System Low Efficiency (Bank 1). Hey guys i have installed 2 new hoses a new water pump, thermostat and flushed the trans.. This is a new customer to me and i do not know if she will be truthful.. After all repair's seemed great test drove and the idle will rise up to 1800 or better.. restart...
November 26, 2012
2007 Ford F-150 King Ranch 5.4L Excessive Emissions, Poor Idle Quality, Misfire, MIL Lamp on VIN: 1FTPW12V17
P0420: Catalyist effeicency below threshold. ... ago with what appeared to be a misfire. We determined that it needed new plugs and boots. After repacement the truck ran better and smoother. Truck was again brought back to us about one month later with a faint gasoline odor in the cab of the truck with t...
November 27, 2012
2007 Ford F-150 King Ranch 5.4L Excessive Emissions, Poor Idle Quality, Misfire, MIL Lamp on VIN: 1FTPW12V17
P0420: Catalyist effeicency below threshold. ... ago with what appeared to be a misfire. We determined that it needed new plugs and boots. After repacement the truck ran better and smoother. Truck was again brought back to us about one month later with a faint gasoline odor in the cab of the truck with t...
November 28, 2012
2005 Dodge Grand Caravan SXT 3.8L MIL Lamp on VIN: 2D8GP44L85
P0420: Catalyst Efficiency Below Normal (Bank 1). Van came in with mil light P 420 checked for O2 switch rate front to back, My genisys, is reading 2.49 volts for a couple seconds and then flashes to -2.51 volts continually, does the same with new sensor,It also, does this weather the van is running or not an...
November 23, 2012
1999 Oldsmobile Aurora 4.0L MIL Lamp on VIN: 1G3GR62C0X
P0420: Catalyst System Low Efficiency (Bank 1). Hey guys i have installed 2 new hoses a new water pump, thermostat and flushed the trans.. This is a new customer to me and i do not know if she will be truthful.. After all repair's seemed great test drove and the idle will rise up to 1800 or better.. restart...
November 26, 2012
2007 Ford F-150 King Ranch 5.4L Excessive Emissions, Poor Idle Quality, Misfire, MIL Lamp on VIN: 1FTPW12V17
P0420: Catalyist effeicency below threshold. ... ago with what appeared to be a misfire. We determined that it needed new plugs and boots. After repacement the truck ran better and smoother. Truck was again brought back to us about one month later with a faint gasoline odor in the cab of the truck with t...
November 27, 2012
2007 Ford F-150 King Ranch 5.4L Excessive Emissions, Poor Idle Quality, Misfire, MIL Lamp on VIN: 1FTPW12V17
P0420: Catalyist effeicency below threshold. ... ago with what appeared to be a misfire. We determined that it needed new plugs and boots. After repacement the truck ran better and smoother. Truck was again brought back to us about one month later with a faint gasoline odor in the cab of the truck with t...
November 28, 2012