Description
OBD-II Trouble Code Description for P0401 Buick
Exhaust Gas Recirculation Flow Insufficient Detected
What does this mean?
OBD2 Code P0401 Buick definition:
EGR stands for Exhaust Gas Recirculation. It is part of the vehicle emmissions system, and is used to reduce combustion temperature and pressure to control Oxides of Nitrogen. There are generally three parts to the EGR system: the EGR valve, an actuator solenoid, and a differential pressure sensor EGR (DPFE). These things work together to deliver the correct amount of recirculation based on engine temperature, load, etc. The P0401 Buick code means that OBD detected an insufficient amount of EGR.
Symptoms
Possible sumptoms of OBD code P0401 Buick
You may notice drivability problems such as pinging (a.k.a. pre-ignition knock) when the engine is under load or the vehicle is at higher speeds. There may also be other symptoms.
Causes
Possible causes of OBD code P0401 Buick
A code P0401 Buick most likely means one or more of the following has happened: ?The DPFE (differential pressure feedback EGR) sensor is faulty and needs to be replaced ?There is a blockage in the EGR (tube), most likely carbon buildup ?The EGR valve is faulty ?The EGR valve may not be opening due to a lack of vaccuum
Possible Solutions
In fixing this code, it is quite common for people to just replace the EGR valve only to have the OBD code return. The EGR valve is not always the culprit. ?Use a vacuum pump and pull the EGR valve open while monitoring engine RPM’s & DPFE voltage. There should be a noticable difference in RPM’s with the EGR open ?Clean out the EGR valve and/or tubing to remove deposits ?Check the voltage at the DPFE, compare to specified values (refer to a repair manual for your specific model) ?Replace the DPFE sensor (with a good quality / OEM one) ?Replace the EGR valve
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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