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SMU - Revised DTC P1404

Subject:Revised DTC P1404

Models:2002-2004 Chevrolet Silverado
2003-2004 Chevrolet Kodiak
2002-2004 GMC Sierra
2003-2004 GMC TopKick
with 6.6L Diesel Engine (VIN 1 - RPO LB7)



This bulletin is being issued to revise Step 4 of DTC P1404 in the Engine Controls sub-section of the Service Manual. Please replace the current information in the Service Manual with the following information.

The following information has been updated within SI. If you are using a paper version of this Service Manual, please make a reference to this bulletin on the affected page.

The component to be tested is the EGR Vacuum Control Solenoid, NOT the EGR Vent Solenoid.

4

Important: Mark all disconnected vacuum hoses for proper installation if necessary.

  1. Disconnect the vacuum hose from the EGR vacuum control solenoid inlet port.
  2. Install a vacuum gage on the inlet port of the EGR vacuum control solenoid.
  3. Apply 15 inches of vacuum. The solenoid should hold vacuum.
  4. Command the EGR Vacuum ON with a scan tool. The EGR vacuum control solenoid should release the vacuum to 0 inches.

Does the EGR vacuum control solenoid operate as described in the above test?

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Go to Step 5

Go to Step 9