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P0420 Diagnostic Trouble Code Discussion for February 2015

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2002 Jaguar X-Type 2.5L Misfire, MIL Lamp on, Limp-home- mode VIN: SAJEB51DX2
... vehicle the Limp-Home- Mode would engage at 3000 rpm to prevent Cat damage,Too many Misfire indications. Actually the vehicle drove and accelerated very well. I cleaned all the grounds in the front of the engine compartment. I performed a smoke ck and reve...
February 11, 2015
2007 Cadillac Escalade 6.2L Poor Idle Quality, MIL Lamp on VIN: 1GYFK63807
P0420: Catalyst System Low Efficiency (Bank 1). ... months ago for a hot stalling and no start that was cured by replacing cam phasers. It has come in many times since for the p0420 and no other codes. Any help would be appreciated. Thanks Tom
February 12, 2015
2002 Jaguar X-Type 2.5L Misfire, MIL Lamp on, Limp-home- mode VIN: SAJEB51DX2
... vehicle the Limp-Home- Mode would engage at 3000 rpm to prevent Cat damage,Too many Misfire indications. Actually the vehicle drove and accelerated very well. I cleaned all the grounds in the front of the engine compartment. I performed a smoke ck and reve...
February 21, 2015
2003 Toyota Camry LE 3.0L MIL Lamp on VIN: 4T1BF32K73
P0420: Catalyst Efficiency Below Normal (Bank 1). ... recurring P0420. It had been setting consistently for months. The oxygen absorption was in the 1-2 second range for both banks, so we replaced them with Walker cats along with the AF and O2 sensors from Denso. A few months later, the code came back and aft...
February 25, 2015