Error code P0404 what is the EGR Valve?

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code p404 Causes and Fixes P0404 Code: Exhaust Gas Recirculation Control Circuit RangePerformance

code p0404 Autohex online Help for members only, Vehicle:SANTAFE Model Year:2012 fault code:p0404  I have a 2006 Jetta TDI DSG BRM engine code Have been having a limp mode issue for awhile I bought the car October 2016 it went into limp mode on the drive