Volkswagen P0479 Exhaust Pressure Control Valve Intermittent

Description

OBD-II Trouble Code Description for P0479 Volkswagen

Exhaust Pressure Control Valve Intermittent

What does this mean?

OBD2 Code P0479 Volkswagen definition:
Exhaust Back Pressure Regulator – Is a variable position valve that controls exhaust back pressure during cold ambient temperatures to increase cab heat and decrease the amount of time needed to defrost the windshield. The PCM uses the measured exhaust back pressure, (ambient) intake air temperature, engine oil temperature and engine load to determine the desired exhaust back pressure. Valve position is controlled by switching the output signal circuit to 12 volts inside the PCM. On/off time is modulated from 0 to 99 % dependent upon the exhaust back pressure desired. Upon each initial engine start-up, the PCM exercises the exhaust back pressure valve by commanding it to cycle on and off once. If upon start-up the temperature of intake air sensed by the IAT sensor is < 37¡ãF (5¡ãC) and the oil temperature sensed by the EOT sensor is between 32¡ã-140¡ãF (0-60¡ãC) it will continue to keep the back pressure valve partially closed. As the oil temperature rises during engine operation, the PCM will control the valve in response to the rising oil temperature.

Symptoms

Possible sumptoms of OBD code P0479 Volkswagen
– Engine Light ON (or Service Engine Soon Warning Light)

Causes

Possible causes of OBD code P0479 Volkswagen
– Exhaust Back Pressure Valve The Error code is generally activated on detection of the following conditions: An open or shorted to ground control circuit can be detected by an on demand output circuit check performed during the engine off test. Problems with either the Exhaust Back Pressure Device or the tube between the exhaust manifold and the EBP sensor can be detected during the exhaust back pressure step test, in which the PCM commands and then measures a specific preprogrammed pressure and then measures time for pressure decay during the engine running test. If the PCM detects an EBP, EOT or IAT sensor fault it will disable the exhaust back pressure regulator.

Possible Solutions

Check the Exhaust Back Pressure Valve (EBPV) butterfly valve is opening and closing freely and not sticking. If it seems to move freely you can then check the connector and circuit for the EBPV solenoid.


The OBD2 Code Information Be Applicable For Volkswagen:

2013 Volkswagen e-Co-Motion Concept,2013 Volkswagen Up 4-door,2013 Volkswagen Up,2013 Volkswagen Touareg Edition X,2013 Volkswagen Scirocco GTS,2013 Volkswagen Santana,2013 Volkswagen Polo R WRC,2013 Volkswagen Polo BlueGT,2013 Volkswagen Passat Alltrack,2013 Volkswagen Lavida,2013 Volkswagen Kombi Last Edition,2013 Volkswagen Jetta Hybrid,2013 Volkswagen Golf Sportsvan Concept,2013 Volkswagen Golf Plus Life,2013 Volkswagen Golf Mk VII UK-Version,2013 Volkswagen Golf GTI Cabriolet,2013 Volkswagen Golf,2013 Volkswagen Gol 2-door,2013 Volkswagen Eco Up,2013 Volkswagen Caddy Cross,2012 Volkswagen Tiguan,2012 Volkswagen Jetta GLI,2012 Volkswagen Beetle,2011 Volkswagen eT Concept,2011 Volkswagen e-Up Concept,2011 Volkswagen XL1 Concept,2011 Volkswagen Touran,2011 Volkswagen Touareg,2011 Volkswagen Sharan,2011 Volkswagen Polo GTI,2011 Volkswagen Phaeton,2011 Volkswagen Jetta,2011 Volkswagen Eos,2011 Volkswagen CrossTouran,2011 Volkswagen CrossPolo,2011 Volkswagen CrossGolf,2011 Volkswagen Amarok,2010 Volkswagen Polo,2010 Volkswagen Golf,2009 Volkswagen Phaeton,2009 Volkswagen Golf,2009 Volkswagen Gol,2008 Volkswagen Phaeton,2008 Volkswagen Golf Variant,2008 Volkswagen Golf GTI Concept,2008 Volkswagen Golf BlueMotion,2007 Volkswagen Up Concept,2007 Volkswagen Touran,2007 Volkswagen Touareg,2007 Volkswagen Eos,2006 Volkswagen Rabbit,2006 Volkswagen Passat,2006 Volkswagen Jetta,2006 Volkswagen Eos,2006 Volkswagen CrossPolo,2005 Volkswagen Touareg,2005 Volkswagen Golf,2005 Volkswagen Fox,2004 Volkswagen RaceTouareg,2004 Volkswagen Golf,2004 Volkswagen Concept T,2004 Volkswagen Concept C,2003 Volkswagen Touran,2003 Volkswagen Passat

 

Note:

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