LEMON Manuals: Even more car manuals for everyone
Home >> Ford >> 2009 >> Flex Limited, FWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 1656 (Engine Controls - Powertrain DTC Charts & Descriptions (Except Diesel & Hybrid)) >> DTC Diagnosis >> DTC P0400: Exhaust Gas RECIRCULATION (EGR) Flow

DTC P0400: Exhaust Gas RECIRCULATION (EGR) Flow

WARNING: This page does not describe the selected car, but rather 33 other vehicles, including the 2010 Mercury Mountaineer, 2010 Mercury Milan, 2010 Mercury Mariner, 2010 Mercury Grand Marquis, and 2010 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.
DTC P0400: EXHAUST GAS RECIRCULATION (EGR) FLOW

Description:  The electric EGR (EEGR) system is monitored once per drive cycle at high and low load conditions. The test fails when a concern is detected by powertrain control module (PCM) calculations indicating the EGR flow is less or greater than expected.
Possible Causes: 
  • EEGR valve stuck open or closed
  • EEGR connector not seated correctly
  • EEGR motor windings short or open
  • No voltage to the EEGR
  • Harness open or short to voltage or ground
  • Vacuum signal to manifold absolute pressure (MAP) restricted or leaking
  • Mass air flow (MAF) sensor signal erroneous
  • Carbon build up in the EEGR valve seat area
  • One or more sensors is not responding or is out of range
Diagnostic Aids:  The following sensors input data to the PCM for correct operation of the EEGR system: engine coolant temperature (ECT), crankshaft position (CKP), intake air temperature (IAT), MAF, throttle position (TP), MAP and vehicle speed sensor (VSS). Any DTC relating to these sensors must be diagnosed prior to addressing this DTC.
Application  Key On Engine Off  Key On Engine Running  Continuous Memory 
All GO to PINPOINT TEST KD .