2 - Fuel System Pressure Test

TOOLS REQUIRED:  SA9127E Gauge Bar Set

This test will determine whether there is adequate fuel pressure delivered to the fuel injectors to start and run the engine under low load conditions.

1. Remove air induction tube.
2. Relieve fuel system pressure. Refer to RELIEVING FUEL PRESSURE .
3. Connect Gauge Bar Set SA9127E and pressure gauge to fuel pressure test port.
   NOTE: Battery must be at a minimum of 12 volts when performing any fuel system test. Charge battery before proceeding if below 12 volts.
4. Energize the fuel pump. Refer to ENERGIZING THE FUEL PUMP  for a minimum of 10 seconds.
   1. Close valve on fuel gauge pressure adapter.
   2. Energize fuel pump.
   3. Record fuel pressure, while fuel pump is energized.
   4. Relieve fuel pressure.
   5. Repeat this procedure a minimum of two times.
      Fig 1: Relieving Fuel Pressure

      Courtesy of GENERAL MOTORS CORP.
5. Compare the pressure recorded to the published specification.
   Fig 2: Published Specification

   Courtesy of GENERAL MOTORS CORP.
6. Return to FUEL SYSTEM DIAGNOSIS - FUEL SUPPLY CHART  and use test result to make appropriate decision.