GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 34730-1A Fuel Pressure Gage

Installation Procedure

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

Caution: Remove the fuel tank cap and relieve the fuel system pressure before servicing the fuel system in order to reduce the risk of personal injury. After you relieve the fuel system pressure, a small amount of fuel may be released when servicing the fuel lines, the fuel injection pump, or the connections. In order to reduce the risk of personal injury, cover the fuel system components with a shop towel before disconnection. This will catch any fuel that may leak out. Place the towel in an approved container when the disconnection is complete.


    Object Number: 180378  Size: SH
  1. Relieve the fuel system pressure. Refer to Fuel Pressure Relief .
  2. Remove the shop towel from around the fuel rail service port, and place in an approved gasoline container.
  3. Perform any tests and/or diagnostics as needed. For the proper usage of the J 34730-1A , refer to the manufacture's directions.

Removal Procedure


    Object Number: 180378  Size: SH
  1. Relieve the fuel system pressure, if required. Perform the following steps:
  2.         Caution: 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 J 34730-1A into an approved gasoline container.
    1.3. Open the valve on the J 34730-1A in order to bleed any fuel from the fuel rail.
    1.4. Close the valve on the J 34730-1A .
    1.5. Remove the hose on the J 34730-1A 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.

    Notice: 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 J 34730-1A from the fuel rail service port.
  4. Install the fuel rail service port cap.
  5. Tighten the fuel fill cap.