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EGR Modulator Check

  1. Check EGR modulator filter for contamination or damage. Clean filter with compressed air.
  2. With engine off, disconnect modulator vacuum hoses (2). Plug one nozzle with finger and blow compressed air into other nozzle. Check that air passes through filter. See Fig 1 .
  3. Warm engine to normal operating temperature. Run engine at 5000 RPM. Using finger, plug one nozzle on modulator. Blow compressed air into other nozzle on modulator.
  4. Check that there is strong resistance to airflow. Reconnect vacuum hoses to each nozzle.
Fig 1: Checking EGR Modulator
G36521