Faulty EGR Valve
Blocked EGR passages
EGR Valve hose connections
EGR Valve harness is ope or shorted
EGR Valve circuit poor electrical connection
Engine Light ON (or Service Engine Soon Warning Light)
EGR System Control Difference is the generic description for the P1403 Audi code, but the manufacturer may have a different description for your model and year vehicle. Currently, we have no further information
about the P1403 Audi OBDII code.