GM Service Manual Online
For 1990-2009 cars only

Special Tools

CH-48027 Digital Pressure Gage

Installation Procedure

Warning: Refer to Gasoline/Gasoline Vapors Warning in the Preface section.

Warning: Refer to Relieving Fuel Pressure Warning in the Preface section.


    Object Number: 1828580  Size: SH
  1. Relieve the fuel system pressure. Refer to Fuel Pressure Relief.
  2. Connect the CH-48027-1 (1) to the CH-48027-2 (2).
  3. Remove the shop towel from around the fuel rail service port, and place in an approved gasoline container.
  4. Perform any tests and/or diagnostics as needed. For the proper usage of the CH-48027 , refer to the manufactures directions.

Removal Procedure


    Object Number: 1828580  Size: SH
  1. Relieve the fuel system pressure, if required. Perform the following steps:
  2.         Warning: Wrap a shop towel around the fuel pressure connection in order to reduce the risk of fire and personal injury. The towel will absorb any fuel leakage that occurs during the connection of the fuel pressure gage. Place the towel in an approved container when the connection of the fuel pressure gage is complete.

    1.1. Wrap a shop towel around the fuel rail service port.
    1.2. Place the hose on the CH-48027-2  (2) into an approved gasoline container.
    1.3. Open the valve on the CH-48027-2  (2) in order to bleed any fuel from the fuel rail.
    1.4. Close the valve on the CH-48027-2  (2).
    1.5. Remove the hose on the CH-48027-2  (2) from the approved gasoline container.
    1.6. Remove the shop towel from around the fuel rail service port, and place in an approved gasoline container.

    Caution: Clean all of the following areas before performing any disconnections in order to avoid possible contamination in the system:

       • The fuel pipe connections
       • The hose connections
       • The areas surrounding the connections

  3. Disconnect the CH-48027-1  (1) from the CH-48027-2  (2).
  4. Disconnect the CH-48027-2  (2) from the CH-48027-3  (4).
  5. Disconnect the CH-48027-3  (4) from the fuel rail service port.
  6. Install the fuel rail service port cap.
  7. Tighten the fuel fill cap.