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Home >> Mazda >> 2005 >> 3 i, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Symptom Troubleshooting [Engine] >> Engine Control System Operation Inspection >> EGR Control System Inspection
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EGR Control System Inspection

  1. Crank the engine and verify that EGR valve operation (initial operation) sound is heard.
    • If the operation sound is not heard, connect the WDS or equivalent to the DLC-2 and verify that the DTC P0403 is shown. Perform DTC inspection. (See DTC TABLE .)
  2. Start the engine and idle it.
  3. Warm up the engine to normal operating temperature.
  4. Access the following PIDs:
    • ECT, RPM, SEGRP_DSD, APP1, APP2, VSS
  5. Idle the vehicle and verify that the SEGRP value is 0.
  6. Put the vehicle in drive.
  7. Depress the accelerator pedal and verify that the SEGRP_DSD value is increased.
    • If the EGR valve increases, inspect the following:
      • EGR valve (stuck open or close)
      • Wiring harness and connectors (Main relay - EGR valve - PCM)
    • If the SEGRP_DSD value does not increase, inspect the VSS, APP1, APP2, TP and ECT PIDs. (See PCM INSPECTION .)
  8. Stop the vehicle and verify that the SEGRP value returns to 0.