GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2006 🢒 STS 🢒 Vehicle Control Systems 🢒 Vehicle DTC Information 🢒 Fuel Pressure Relief

Tools Required

    • J 34730-1A Fuel Pressure Gage
    • J 42242 Fuel Pressure Gage Adapter

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: Relieve the fuel system pressure before servicing fuel system components in order to reduce the risk of fire and personal injury.

After relieving the system pressure, a small amount of fuel may be released when servicing the fuel lines or connections. In order to reduce the chance of personal injury, cover the regulator and the fuel line fittings with a shop towel before disconnecting. This will catch any fuel that may leak out. Place the towel in an approved container when the disconnection is complete.


    Object Number: 1652887 Size: SH
  1. Turn the ignition OFF.
  2. Disconnect the negative battery cable in order to avoid possible fuel discharge if an accidental attempt is made to start the engine. Refer to Battery Negative Cable Disconnection and Connection .
  3. Remove the engine sight shield. Refer to Intake Manifold Sight Shield Replacement .
  4. Remove the cap from the fuel pressure test port valve on the fuel rail.

    5. Object Number: 1652917 Size: SH
  5. Connect the J 42242  (1) to the fuel pressure test port valve. Wrap a shop towel around the fitting while connecting the adapter in order to avoid spillage.
  6. Connect the J 34730-1A  (2) to the J 42242  (1). Wrap a shop towel around the fittings while connecting the gage to the adapter in order to avoid spillage.
  7. Install the bleed hose into an approved container.
  8. Open the valve in order to bleed the system pressure. Fuel connections are now safe for servicing.
  9. Drain any fuel remaining in the gage into an approved container.
  10. Remove the J 34730-1A and the J 42242 .
  11. Install the cap to the fuel pressure test port valve.
  12. Install the engine sight shield. Refer to Intake Manifold Sight Shield Replacement .
  13. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection .