LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Ford >> 2023 >> Escape ST-Line Select >> Repair and Diagnosis >> External Pages >> Different car >> Section 12 (Engine Controls - Powertrain DTC Charts & Descriptions (Diesel)) >> Diagnostic Trouble Code (DTC) Charts And Descriptions >> DTC P0401 - EGR A Flow Insufficient Detected
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC P0401 - EGR A Flow Insufficient Detected

WARNING: This page does not describe the selected car, but rather 9 other vehicles, including the 2018 Ford Transit-350 HD, 2018 Ford Transit-350, 2018 Ford Transit-250, 2018 Ford Transit-150, and 2018 Ford F-550 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.
P0401 - EGR A FLOW INSUFFICIENT DETECTED

Description:  This DTC sets 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. The estimated EGR percent is less than the minimum limit for the operating conditions.
Possible Causes: 
  • Aftermarket intake systems or exhaust systems
  • Restricted airflow (intake or exhaust)
  • Restricted EGR cooler
  • EGR valve position sensor bias
  • EP sensor bias
  • MAP sensor bias
  • Damaged EGR valve
Diagnostic Aids:  The presence of this DTC may indicate that the vehicle is operating in derate mode and may experience a loss of power. After repair, the vehicle may still display a system warning message. Drive the vehicle until the system warning message has cleared from the instrument cluster message center.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to PINPOINT TEST W .