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Home >> Ford >> 2002 >> Cutaway 7.3 F >> Repair and Diagnosis >> External Pages >> Different car >> Section 2376 (Engine Controls - Diagnostic Subroutines - 6.4L 99R Diesel -- F250-F550 Super Duty) >> Diagnostic Trouble Code (DTC) Charts and Descriptions >> P0401 - Exhaust Gas RECIRCULATION (EGR) Flow Insufficient Detected

P0401 - Exhaust Gas RECIRCULATION (EGR) Flow Insufficient Detected

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P0401 - EXHAUST GAS RECIRCULATION (EGR) FLOW INSUFFICIENT DETECTED

Description:  Estimated EGR percent is less than the minimum limit for the operating conditions.
Possible Causes: 
  • Aftermarket intake systems or exhaust systems
  • Restricted air flow (intake or exhaust)
  • Restricted EGR cooler
  • EGR valve position sensor bias
  • Exhaust pressure (EP) sensor bias
  • Manifold absolute pressure (MAP) sensor bias
  • EGR valve
Diagnostic Aids:  This DTC is set when the pressure ratio of the manifold absolute pressure (MAP) sensor signal and the exhaust pressure (EP) sensor signal across the EGR valve is not as expected.
Application    Key On Engine Off  Key On Engine Running  Continuous Memory 
All   refer to PINPOINT TEST W .