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Home >> Mitsubishi >> 2003 >> Eclipse RS, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics - 2.4L >> Diagnostic Tests >> DTC P0401: EGR Insufficient Flow Detected >> Diagnostic Procedure
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Diagnostic Procedure

  1. Check the EGR system. See EXHAUST GAS RECIRCULATION (EGR) under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING article. If there are any abnormalities, rectify and proceed to step  3 . If the system looks normal, go to the next step.
  2. Connect scan tool (MB991502) to the data link connector. Start the engine and run at idle. Set the scan tool to data reading mode for item 95, Manifold Differential Pressure Sensor. Warm up the engine to normal operating temperature: 176-205°F (80-96°C). At engine idle, the resistance should be 65-78 kPa. Turn the ignition off. If the sensor is operating properly, clean the EGR valve and EGR passage and go to the next step. If the sensor is malfunctioning, refer to DTC P1400: MANIFOLD DIFFERENTIAL PRESSURE (MDP) SENSOR CIRCUIT MALFUNCTION  .
  3. Carry out a test drive with the drive cycle pattern, refer to EGR MONITOR  . Check the diagnostic trouble codes. If DTC P0401 is output, retry the troubleshooting. If the DTC is absent, the inspection is complete.
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