Tools Required

J 34730-1A  Fuel Pressure Gage

Fig 1: Identifying Fuel Pressure Gauge J 34730-1A
Courtesy of GENERAL MOTORS CORP.
1. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical.
2. Remove the fuel injector sight shield. Refer to Fuel Injector Sight Shield Replacement (L36) or Fuel Injector Sight Shield Replacement (L67) in Engine Mechanical - 3.8L.
3. Loosen the fuel filler cap to relieve tank vapor pressure.
4. Connect the J 34730-1A  to the fuel pressure connection. Wrap a shop towel around the fuel pressure connection while connecting the fuel pressure gauge in order to avoid spillage.
5. Install the bleed hose into an approved container and open the valve to bleed the system pressure. The fuel connections are now safe for servicing.
6. Drain any fuel remaining in the fuel pressure gauge into an approved container.