GM Service Manual Online
For 1990-2009 cars only

Tools Required

J-34730-FF Fuel Pressure Gage

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.

  1. Turn OFF the ignition.
  2. Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

  3. Disconnect the negative battery cable in order to avoid possible fuel discharge if an accidental attempt is made to start the engine.
  4. Loosen the fuel filler cap in order to relieve the fuel tank vapor pressure.

  5. Object Number: 638720  Size: SH
  6. Connect the J-34730-FF to the fuel pressure connection. Wrap a shop towel around the fitting while connecting the gauge in order to avoid spillage.
  7. Install the bleed hose of the gauge into an approved container.
  8. Open the valve on the gauge to bleed the system pressure.
  9. Drain any fuel remaining in the fuel pressure gauge into an approved container.