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Home >> Ford >> 2000 >> Contour SE, 2.5 L, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 753 (Engine Controls - Powertrain DTC Charts & Descriptions - CNG, Flex-Fuel & Gasoline) >> Diagnostic Trouble Code (DTC) Charts >> P0401: EGR Flow Insufficient Detected

P0401: EGR Flow Insufficient Detected

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P0401 - EGR FLOW INSUFFICIENT DETECTED

Description:  The EGR system is monitored during steady state driving conditions while the EGR is commanded on. The test fails when the signal from the Differential Pressure Feedback EGR sensor indicates that EGR flow is less than the desired minimum.
Possible Causes: 
  • Vacuum supply.
  • EGR valve stuck closed.
  • EGR valve leaks vacuum.
  • EGR flow path restricted.
  • EGRVR circuit shorted to PWR.
  • VREF open to DPFEGR sensor.
  • DPFEGR sensor downstream hose is off or plugged.
  • EGRVR circuit open to the PCM.
  • VPWR open to EGRVR solenoid.
  • DPFEGR sensor hoses are both off.
  • DPFEGR sensor hoses are reversed.
  • Damaged EGR orifice tube.
  • Damaged EGRVR solenoid.
  • Damaged PCM.
Diagnostic Aids:  Perform the KOER self-test and look for DTC P1408 as an indication of a hard fault. If P1408 is not present, look for contamination, restrictions, leaks, and intermittents.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
Vehicles with an EGR System Module (ESM) - - GO to PINPOINT TEST HH: EXHAUST GAS RECIRCULATION SYSTEM MODULE (ESM) Step 16.
All others - - GO to PINPOINT TEST HE: EXHAUST GAS RECIRCULATION (EGR) SYSTEMS Step 36.
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