GM Service Manual Online
For 1990-2009 cars only

Tools Required

J-34730-FF Fuel Pressure Gage

Installation Procedure

Caution: Gasoline or gasoline vapors are highly flammable. A fire could occur if an ignition source is present. Never drain or store gasoline or diesel fuel in an open container, due to the possibility of fire or explosion. Have a dry chemical (Class B) fire extinguisher nearby.

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.

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


    Object Number: 180378  Size: SH
  1. Install the J-34730-FF to the fuel pressure service connection, located on the fuel rail.
  2. Turn ON the ignition, with the engine OFF.
  3. Caution: Do not drain the fuel into an open container. Never store the fuel in an open container due to the possibility of a fire or an explosion.

  4. Place the bleed hose of the fuel pressure gage into an approved gasoline container.
  5. Open the bleed valve on the fuel pressure gage in order to bleed the air from the fuel pressure gage.
  6. Command the fuel pump ON with a scan tool.
  7. Close the bleed valve on the fuel pressure gage.
  8. Command the fuel pump ON with a scan tool.
  9. Inspect for fuel leaks.

Removal Procedure

  1. Place the fuel pressure gage bleed hose into an approved container and open the bleed valve to bleed OFF fuel system pressure.
  2. Place a shop towel under the to catch any remaining fuel spillage.

  3. Object Number: 180378  Size: SH
  4. Remove the from the fuel pressure connection.
  5. Drain any fuel remaining in the fuel pressure gage into an approved container.
  6. Inspect for leaks using the following procedure:
  7. 5.1. Turn ON the ignition, with the engine OFF for 2 seconds.
    5.2. Turn OFF the ignition, for 10 seconds.
    5.3. Turn ON the ignition, with the engine OFF.
    5.4. Inspect for fuel leaks.
  8. Install the cap on the fuel pressure connection.