[red4x4]

Have f150 97' 4.6liter with a fault code of p0401. Have already replaced EGR Valve , Air Idle Sensor, cleaned Mass Airflow Sensor,cleaned idle position sensor. Cant seem to find problem. Can anyone help

 

[Mr Mac]

Have you also checked/replaced the EGR vacuum regulator solenoid and clean the back pressure transducer tubes along with their ports and the manifold tube?


DTC Code: P0401 Description: Exhaust Gas Recirculation Flow Insufficient Detected Probable Causes:

1. Sensor or solenoid faulty
2. Connector terminal contact is damaged or corroded
3. Wire harness - Check harness for correct voltage, open, short to ground or short to voltage
4. Update control unit software - Check for the latest control unit update
5. Powertrain or Engine Control Module faulty
6. Exhaust leaks or restrictions
7. EGR components clogged, dirty or leaky
8. EGR valve damaged/defective