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Home >> Cadillac >> 2002 >> Escalade EXT >> Repair and Diagnosis >> External Pages >> Different car >> Section 88 (Engine Control System Self-Diagnostics - 3.8L) >> Diagnostic Tests >> DTC P0404: EGR Open Position Performance >> Test Description
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Test Description

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The numbers below refer to the step numbers in the diagnostic procedures.

  1. 2

    This step verifies that the malfunction is present.
  2. 3

    If DTC P0404 will only set under certain conditions, the malfunction may be intermittent. See DIAGNOSTIC AIDS . If an intermittent wiring problem is not present, test for a faulty connection at the PCM or the EGR valve. If the connections are okay and DTC P0404 continues to set, replace the EGR valve.