Description
OBD-II Trouble Code Description for P0421 Buick
Warm Up Catalyst Efficiency Below Threshold
What does this mean?
OBD2 Code P0421 Buick definition:
Basically this means that the oxygen sensor downstream of the catalytic converter on bank 1 is detecting that the converter is not working as efficiently as it should be (according to specs). It is part of the vehicle emissions system.
Symptoms
Possible sumptoms of OBD code P0421 Buick
You will likely not notice any drivability problems, although there may be symptoms. The code may be more likely to occur after the engine has had numerous cold starts in the past 1-2 days.
Causes
Possible causes of OBD code P0421 Buick
A code P0421 Buick may mean that one or more of the following has happened: The catalytic converter is no longer functioning properly An oxygen sensor is not reading (functioning) properly A sparkplug is fouled up
Possible Solutions
Measure the voltage at the oxygen sensor on Bank 1 (the rear sensor, or the sensor after the converter). In fact, it would be a good idea to test each oxygen O2 sensor while you’re at it. One thing to note is that many vehicle manufacturers offer a longer warranty on emissions-related parts. So if you have a newer car but it’s out of it’s bumper-to-bumper warranty, there still may be warranty on this type of problem. Many manufacturers give a five year, unlimited mileage warranty on these items. It’s worth checking into.
The OBD2 Code Information Be Applicable For Buick
2013 Buick Verano Turbo,2013 Buick Riviera Concept,2013 Buick Encore,2013 Buick Enclave,2012 Buick Verano,2012 Buick Regal GS,2011 Buick Regal,2011 Buick LaCrosse GL Concept,2011 Buick GL8,2011 Buick Envision Concept,2010 Buick Regal GS Concept,2010 Buick LaCrosse,2009 Buick Business Concept,2008 Buick Lucerne Super,2008 Buick LaCrosse Super,2008 Buick LaCrosse CXS,2008 Buick Invicta Concept,2008 Buick Enclave,2007 Buick Riviera Concept Coupe,2006 Buick Terraza,2006 Buick Rendezvous CXL,2006 Buick Rainier CXL,2006 Buick Lucerne CXS,2006 Buick Enclave Concept,2005 Buick Terraza CXL,2005 Buick Royaum,2005 Buick Rendezvous CX,2005 Buick Park Avenue,2005 Buick LeSabre Celebration Edition,2005 Buick LaCrosse CXS,2005 Buick LaCrosse CSX,2005 Buick Century,2004 Buick Velite Concept,2004 Buick Rendezvous Ultra,2004 Buick Regal Abboud GS,2004 Buick Rainier,2004 Buick Park Avenue Ultra,2003 Buick Rendezvous,2003 Buick Park Avenue Ultra,2002 Buick Rendezvous,2002 Buick Regal,2002 Buick LeSabre Custom,2001 Buick Regal,2001 Buick Park Avenue Ultra,2001 Buick Park Avenue,2001 Buick LeSabre,2001 Buick Blackhawk Concept,2001 Buick 2-2 Bengal Roadster Concept,2000 Buick Regal GNX Show Car,2000 Buick Regal Cielo Concept,2000 Buick Regal,2000 Buick Park Avenue,2000 Buick LeSabre Limited,2000 Buick Century
Note:
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